exploratory

* Closes 542.

Fast fields are all loaded when the segment reader is created.

.travis.yml

@@ -29,7 +29,7 @@ addons:
 matrix:
   include:
     # Android
-    - env: TARGET=aarch64-linux-android DISABLE_TESTS
+    - env: TARGET=aarch64-linux-android DISABLE_TESTS=1
     #- env: TARGET=arm-linux-androideabi DISABLE_TESTS=1
     #- env: TARGET=armv7-linux-androideabi DISABLE_TESTS=1
     #- env: TARGET=i686-linux-android DISABLE_TESTS=1
@@ -68,6 +68,11 @@ cache: cargo
 before_cache:
   # Travis can't cache files that are not readable by "others"
   - chmod -R a+r $HOME/.cargo
+  - find ./target/debug -type f -maxdepth 1 -delete
+  - rm -f  ./target/.rustc_info.json
+  - rm -fr ./target/debug/{deps,.fingerprint}/tantivy*
+  - rm -r target/debug/examples/
+  - ls -1 examples/ | sed -e 's/\.rs$//' | xargs -I "{}" find target/* -name "*{}*" -type f -delete
 
 #branches:
 #  only:

CHANGELOG.md

@@ -1,3 +1,35 @@
+Tantivy 0.10.0
+=====================
+
+*Tantivy 0.10.0 index format is compatible with the index format in 0.9.0.*
+
+- Added an ASCII folding filter (@drusellers)
+- Bugfix in `query.count` in presence of deletes (@pmasurel)
+
+Minor
+---------
+- Small simplification of the code. 
+Calling .freq() or .doc() when .advance() has never 
+on segment postings should panic from now on.
+- Tokens exceeding `u16::max_value() - 4` chars are discarded silently instead of panicking.
+- Fast fields are now preloaded when the `SegmentReader` is created.
+
+## How to update?
+
+Your existing indexes are usable as is. Your may or may need some 
+trivial updates.
+
+### Fast fields
+
+Fast fields used to be accessed directly from the `SegmentReader`.
+The API changed, you are now required to acquire your fast field reader via the
+`segment_reader.fast_fields()`, and use one of the typed method: 
+- `.u64()`, `.i64()` if your field is single-valued ;
+- `.u64s()`, `.i64s()` if your field is multi-valued ;
+- `.bytes()` if your field is bytes fast field.
+
+
+
 Tantivy 0.9.0
 =====================
 *0.9.0 index format is not compatible with the 
@@ -17,6 +49,35 @@ previous index format.*
 - Added IndexReader. By default, index is reloaded automatically upon new commits (@fulmicoton)
 - SIMD linear search within blocks (@fulmicoton)
 
+## How to update ?
+
+tantivy 0.9 brought some API breaking change.
+To update from tantivy 0.8, you will need to go through the following steps.
+
+- `schema::INT_INDEXED` and `schema::INT_STORED`  should be replaced by `schema::INDEXED` and `schema::INT_STORED`.
+- The index now does not hold the pool of searcher anymore. You are required to create an intermediary object called 
+`IndexReader` for this. 
+    
+    ```rust
+    // create the reader. You typically need to create 1 reader for the entire
+    // lifetime of you program.
+    let reader = index.reader()?;
+    
+    // Acquire a searcher (previously `index.searcher()`) is now written:
+    let searcher = reader.searcher();
+    
+    // With the default setting of the reader, you are not required to 
+    // call `index.load_searchers()` anymore.
+    //
+    // The IndexReader will pick up that change automatically, regardless
+    // of whether the update was done in a different process or not.
+    // If this behavior is not wanted, you can create your reader with 
+    // the `ReloadPolicy::Manual`, and manually decide when to reload the index
+    // by calling `reader.reload()?`.
+  
+    ```
+
+
 Tantivy 0.8.2
 =====================
 Fixing build for x86_64 platforms. (#496)

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "tantivy"
-version = "0.9.0"
+version = "0.10.0-dev"
 authors = ["Paul Masurel <paul.masurel@gmail.com>"]
 license = "MIT"
 categories = ["database-implementations", "data-structures"]
@@ -23,7 +23,7 @@ snap = {version="0.2"}
 atomicwrites = {version="0.2.2", optional=true}
 tempfile = "3.0"
 log = "0.4"
-combine = "3"
+combine = ">=3.6.0,<4.0.0"
 tempdir = "0.3"
 serde = "1.0"
 serde_derive = "1.0"

examples/custom_collector.rs

@@ -18,8 +18,8 @@ use tantivy::fastfield::FastFieldReader;
 use tantivy::query::QueryParser;
 use tantivy::schema::Field;
 use tantivy::schema::{Schema, FAST, INDEXED, TEXT};
-use tantivy::Index;
 use tantivy::SegmentReader;
+use tantivy::{Index, TantivyError};
 
 #[derive(Default)]
 struct Stats {
@@ -75,9 +75,18 @@ impl Collector for StatsCollector {
     fn for_segment(
         &self,
         _segment_local_id: u32,
-        segment: &SegmentReader,
+        segment_reader: &SegmentReader,
     ) -> tantivy::Result<StatsSegmentCollector> {
-        let fast_field_reader = segment.fast_field_reader(self.field)?;
+        let fast_field_reader = segment_reader
+            .fast_fields()
+            .u64(self.field)
+            .ok_or_else(|| {
+                let field_name = segment_reader.schema().get_field_name(self.field);
+                TantivyError::SchemaError(format!(
+                    "Field {:?} is not a u64 fast field.",
+                    field_name
+                ))
+            })?;
         Ok(StatsSegmentCollector {
             fast_field_reader,
             stats: Stats::default(),

src/collector/facet_collector.rs

@@ -17,6 +17,7 @@ use Result;
 use Score;
 use SegmentLocalId;
 use SegmentReader;
+use TantivyError;
 
 struct Hit<'a> {
     count: u64,
@@ -264,7 +265,10 @@ impl Collector for FacetCollector {
         _: SegmentLocalId,
         reader: &SegmentReader,
     ) -> Result<FacetSegmentCollector> {
-        let facet_reader = reader.facet_reader(self.field)?;
+        let field_name = reader.schema().get_field_name(self.field);
+        let facet_reader = reader.facet_reader(self.field).ok_or_else(|| {
+            TantivyError::SchemaError(format!("Field {:?} is not a facet field.", field_name))
+        })?;
 
         let mut collapse_mapping = Vec::new();
         let mut counts = Vec::new();

src/collector/multi_collector.rs

@@ -2,6 +2,7 @@ use super::Collector;
 use super::SegmentCollector;
 use collector::Fruit;
 use std::marker::PhantomData;
+use std::ops::Deref;
 use DocId;
 use Result;
 use Score;
@@ -199,7 +200,10 @@ impl<'a> Collector for MultiCollector<'a> {
     }
 
     fn requires_scoring(&self) -> bool {
-        self.collector_wrappers.iter().any(|c| c.requires_scoring())
+        self.collector_wrappers
+            .iter()
+            .map(Deref::deref)
+            .any(Collector::requires_scoring)
     }
 
     fn merge_fruits(&self, segments_multifruits: Vec<MultiFruit>) -> Result<MultiFruit> {

src/collector/tests.rs

@@ -114,11 +114,15 @@ impl Collector for FastFieldTestCollector {
     fn for_segment(
         &self,
         _: SegmentLocalId,
-        reader: &SegmentReader,
+        segment_reader: &SegmentReader,
     ) -> Result<FastFieldSegmentCollector> {
+        let reader = segment_reader
+            .fast_fields()
+            .u64(self.field)
+            .expect("Requested field is not a fast field.");
         Ok(FastFieldSegmentCollector {
             vals: Vec::new(),
-            reader: reader.fast_field_reader(self.field)?,
+            reader,
         })
     }
 
@@ -170,11 +174,14 @@ impl Collector for BytesFastFieldTestCollector {
     fn for_segment(
         &self,
         _segment_local_id: u32,
-        segment: &SegmentReader,
+        segment_reader: &SegmentReader,
     ) -> Result<BytesFastFieldSegmentCollector> {
         Ok(BytesFastFieldSegmentCollector {
             vals: Vec::new(),
-            reader: segment.bytes_fast_field_reader(self.field)?,
+            reader: segment_reader
+                .fast_fields()
+                .bytes(self.field)
+                .expect("Field is not a bytes fast field."),
         })
     }
 
@@ -191,7 +198,7 @@ impl SegmentCollector for BytesFastFieldSegmentCollector {
     type Fruit = Vec<u8>;
 
     fn collect(&mut self, doc: u32, _score: f32) {
-        let data = self.reader.get_val(doc);
+        let data = self.reader.get_bytes(doc);
         self.vals.extend(data);
     }
 

src/collector/top_collector.rs

@@ -98,11 +98,11 @@ where
             .collect())
     }
 
-    pub(crate) fn for_segment(
+    pub(crate) fn for_segment<F: PartialOrd>(
         &self,
         segment_id: SegmentLocalId,
         _: &SegmentReader,
-    ) -> Result<TopSegmentCollector<T>> {
+    ) -> Result<TopSegmentCollector<F>> {
         Ok(TopSegmentCollector::new(segment_id, self.limit))
     }
 }

src/collector/top_field_collector.rs

@@ -5,10 +5,12 @@ use collector::SegmentCollector;
 use fastfield::FastFieldReader;
 use fastfield::FastValue;
 use schema::Field;
+use std::marker::PhantomData;
 use DocAddress;
 use Result;
 use SegmentLocalId;
 use SegmentReader;
+use TantivyError;
 
 /// The Top Field Collector keeps track of the K documents
 /// sorted by a fast field in the index
@@ -106,8 +108,15 @@ impl<T: FastValue + PartialOrd + Send + Sync + 'static> Collector for TopDocsByF
         reader: &SegmentReader,
     ) -> Result<TopFieldSegmentCollector<T>> {
         let collector = self.collector.for_segment(segment_local_id, reader)?;
-        let reader = reader.fast_field_reader(self.field)?;
+        let reader = reader.fast_fields().u64(self.field).ok_or_else(|| {
-        Ok(TopFieldSegmentCollector { collector, reader })
+            let field_name = reader.schema().get_field_name(self.field);
+            TantivyError::SchemaError(format!("Failed to find fast field reader {:?}", field_name))
+        })?;
+        Ok(TopFieldSegmentCollector {
+            collector,
+            reader,
+            _type: PhantomData,
+        })
     }
 
     fn requires_scoring(&self) -> bool {
@@ -122,9 +131,10 @@ impl<T: FastValue + PartialOrd + Send + Sync + 'static> Collector for TopDocsByF
     }
 }
 
-pub struct TopFieldSegmentCollector<T: FastValue + PartialOrd> {
+pub struct TopFieldSegmentCollector<T> {
-    collector: TopSegmentCollector<T>,
+    collector: TopSegmentCollector<u64>,
-    reader: FastFieldReader<T>,
+    reader: FastFieldReader<u64>,
+    _type: PhantomData<T>,
 }
 
 impl<T: FastValue + PartialOrd + Send + Sync + 'static> SegmentCollector
@@ -138,7 +148,11 @@ impl<T: FastValue + PartialOrd + Send + Sync + 'static> SegmentCollector
     }
 
     fn harvest(self) -> Vec<(T, DocAddress)> {
-        self.collector.harvest()
+        self.collector
+            .harvest()
+            .into_iter()
+            .map(|(val, doc_address)| (T::from_u64(val), doc_address))
+            .collect()
     }
 }
 
@@ -235,7 +249,7 @@ mod tests {
                 .for_segment(0, segment)
                 .map(|_| ())
                 .unwrap_err(),
-            TantivyError::FastFieldError(_)
+            TantivyError::SchemaError(_)
         );
     }
 

src/common/mod.rs

@@ -13,7 +13,6 @@ pub use self::serialize::{BinarySerializable, FixedSize};
 pub use self::vint::{read_u32_vint, serialize_vint_u32, write_u32_vint, VInt};
 pub use byteorder::LittleEndian as Endianness;
 
-
 /// Segment's max doc must be `< MAX_DOC_LIMIT`.
 ///
 /// We do not allow segments with more than

src/core/index.rs

@@ -340,7 +340,7 @@ impl Index {
         Ok(self
             .searchable_segment_metas()?
             .iter()
-            .map(|segment_meta| segment_meta.id())
+            .map(SegmentMeta::id)
             .collect())
     }
 }

src/core/searcher.rs

@@ -59,7 +59,7 @@ impl Searcher {
     ) -> Searcher {
         let store_readers = segment_readers
             .iter()
-            .map(|segment_reader| segment_reader.get_store_reader())
+            .map(SegmentReader::get_store_reader)
             .collect();
         Searcher {
             schema,
@@ -218,7 +218,7 @@ impl fmt::Debug for Searcher {
         let segment_ids = self
             .segment_readers
             .iter()
-            .map(|segment_reader| segment_reader.segment_id())
+            .map(SegmentReader::segment_id)
             .collect::<Vec<_>>();
         write!(f, "Searcher({:?})", segment_ids)
     }

src/core/segment_reader.rs

@@ -5,14 +5,10 @@ use core::Segment;
 use core::SegmentComponent;
 use core::SegmentId;
 use directory::ReadOnlySource;
-use error::TantivyError;
 use fastfield::DeleteBitSet;
 use fastfield::FacetReader;
-use fastfield::FastFieldReader;
+use fastfield::FastFieldReaders;
-use fastfield::{self, FastFieldNotAvailableError};
-use fastfield::{BytesFastFieldReader, FastValue, MultiValueIntFastFieldReader};
 use fieldnorm::FieldNormReader;
-use schema::Cardinality;
 use schema::Field;
 use schema::FieldType;
 use schema::Schema;
@@ -51,7 +47,7 @@ pub struct SegmentReader {
     postings_composite: CompositeFile,
     positions_composite: CompositeFile,
     positions_idx_composite: CompositeFile,
-    fast_fields_composite: CompositeFile,
+    fast_fields_readers: Arc<FastFieldReaders>,
     fieldnorms_composite: CompositeFile,
 
     store_source: ReadOnlySource,
@@ -105,93 +101,21 @@ impl SegmentReader {
     ///
     /// # Panics
     /// May panic if the index is corrupted.
-    pub fn fast_field_reader<Item: FastValue>(
+    pub fn fast_fields(&self) -> &FastFieldReaders {
-        &self,
+        &self.fast_fields_readers
-        field: Field,
-    ) -> fastfield::Result<FastFieldReader<Item>> {
-        let field_entry = self.schema.get_field_entry(field);
-        if Item::fast_field_cardinality(field_entry.field_type()) == Some(Cardinality::SingleValue)
-        {
-            self.fast_fields_composite
-                .open_read(field)
-                .ok_or_else(|| FastFieldNotAvailableError::new(field_entry))
-                .map(FastFieldReader::open)
-        } else {
-            Err(FastFieldNotAvailableError::new(field_entry))
-        }
-    }
-
-    pub(crate) fn fast_field_reader_with_idx<Item: FastValue>(
-        &self,
-        field: Field,
-        idx: usize,
-    ) -> fastfield::Result<FastFieldReader<Item>> {
-        if let Some(ff_source) = self.fast_fields_composite.open_read_with_idx(field, idx) {
-            Ok(FastFieldReader::open(ff_source))
-        } else {
-            let field_entry = self.schema.get_field_entry(field);
-            Err(FastFieldNotAvailableError::new(field_entry))
-        }
-    }
-
-    /// Accessor to the `MultiValueIntFastFieldReader` associated to a given `Field`.
-    /// May panick if the field is not a multivalued fastfield of the type `Item`.
-    pub fn multi_fast_field_reader<Item: FastValue>(
-        &self,
-        field: Field,
-    ) -> fastfield::Result<MultiValueIntFastFieldReader<Item>> {
-        let field_entry = self.schema.get_field_entry(field);
-        if Item::fast_field_cardinality(field_entry.field_type()) == Some(Cardinality::MultiValues)
-        {
-            let idx_reader = self.fast_field_reader_with_idx(field, 0)?;
-            let vals_reader = self.fast_field_reader_with_idx(field, 1)?;
-            Ok(MultiValueIntFastFieldReader::open(idx_reader, vals_reader))
-        } else {
-            Err(FastFieldNotAvailableError::new(field_entry))
-        }
-    }
-
-    /// Accessor to the `BytesFastFieldReader` associated to a given `Field`.
-    pub fn bytes_fast_field_reader(&self, field: Field) -> fastfield::Result<BytesFastFieldReader> {
-        let field_entry = self.schema.get_field_entry(field);
-        match *field_entry.field_type() {
-            FieldType::Bytes => {}
-            _ => return Err(FastFieldNotAvailableError::new(field_entry)),
-        }
-        let idx_reader = self
-            .fast_fields_composite
-            .open_read_with_idx(field, 0)
-            .ok_or_else(|| FastFieldNotAvailableError::new(field_entry))
-            .map(FastFieldReader::open)?;
-        let values = self
-            .fast_fields_composite
-            .open_read_with_idx(field, 1)
-            .ok_or_else(|| FastFieldNotAvailableError::new(field_entry))?;
-        Ok(BytesFastFieldReader::open(idx_reader, values))
     }
 
     /// Accessor to the `FacetReader` associated to a given `Field`.
-    pub fn facet_reader(&self, field: Field) -> Result<FacetReader> {
+    pub fn facet_reader(&self, field: Field) -> Option<FacetReader> {
         let field_entry = self.schema.get_field_entry(field);
         if field_entry.field_type() != &FieldType::HierarchicalFacet {
-            return Err(TantivyError::InvalidArgument(format!(
+            return None;
-                "The field {:?} is not a \
-                 hierarchical facet.",
-                field_entry
-            )));
         }
-        let term_ords_reader = self.multi_fast_field_reader(field)?;
+        let term_ords_reader = self.fast_fields().u64s(field)?;
-        let termdict_source = self.termdict_composite.open_read(field).ok_or_else(|| {
+        let termdict_source = self.termdict_composite.open_read(field)?;
-            TantivyError::InvalidArgument(format!(
-                "The field \"{}\" is a hierarchical \
-                 but this segment does not seem to have the field term \
-                 dictionary.",
-                field_entry.name()
-            ))
-        })?;
         let termdict = TermDictionary::from_source(&termdict_source);
         let facet_reader = FacetReader::new(term_ords_reader, termdict);
-        Ok(facet_reader)
+        Some(facet_reader)
     }
 
     /// Accessor to the segment's `Field norms`'s reader.
@@ -247,8 +171,12 @@ impl SegmentReader {
             }
         };
 
+        let schema = segment.schema();
+
         let fast_fields_data = segment.open_read(SegmentComponent::FASTFIELDS)?;
         let fast_fields_composite = CompositeFile::open(&fast_fields_data)?;
+        let fast_field_readers =
+            Arc::new(FastFieldReaders::load_all(&schema, &fast_fields_composite)?);
 
         let fieldnorms_data = segment.open_read(SegmentComponent::FIELDNORMS)?;
         let fieldnorms_composite = CompositeFile::open(&fieldnorms_data)?;
@@ -260,14 +188,13 @@ impl SegmentReader {
             None
         };
 
-        let schema = segment.schema();
         Ok(SegmentReader {
             inv_idx_reader_cache: Arc::new(RwLock::new(HashMap::new())),
             max_doc: segment.meta().max_doc(),
             num_docs: segment.meta().num_docs(),
             termdict_composite,
             postings_composite,
-            fast_fields_composite,
+            fast_fields_readers: fast_field_readers,
             fieldnorms_composite,
             segment_id: segment.id(),
             store_source,
@@ -381,12 +308,12 @@ impl SegmentReader {
             self.postings_composite.space_usage(),
             self.positions_composite.space_usage(),
             self.positions_idx_composite.space_usage(),
-            self.fast_fields_composite.space_usage(),
+            self.fast_fields_readers.space_usage(),
             self.fieldnorms_composite.space_usage(),
             self.get_store_reader().space_usage(),
             self.delete_bitset_opt
                 .as_ref()
-                .map(|x| x.space_usage())
+                .map(DeleteBitSet::space_usage)
                 .unwrap_or(0),
         )
     }

src/directory/directory.rs

@@ -205,16 +205,6 @@ pub trait Directory: DirectoryClone + fmt::Debug + Send + Sync + 'static {
     /// `OnCommit` `ReloadPolicy`. Not implementing watch in a `Directory` only prevents the
     /// `OnCommit` `ReloadPolicy` to work properly.
     fn watch(&self, watch_callback: WatchCallback) -> WatchHandle;
-
-    /// Ensure that all volatile files reach are persisted (in directory where that makes sense.)
-    ///
-    /// In order to make Near Real Time efficient, tantivy introduced the notion of soft_commit vs
-    /// commit. Commit will call `.flush()`, while softcommit won't.
-    ///
-    /// `meta.json` should be the last file to be flushed.
-    fn flush(&self) -> io::Result<()> {
-        Ok(())
-    }
 }
 
 /// DirectoryClone

src/directory/mmap_directory.rs

@@ -368,7 +368,7 @@ impl Drop for ReleaseLockFile {
 
 /// This Write wraps a File, but has the specificity of
 /// call `sync_all` on flush.
-pub struct SafeFileWriter(File);
+struct SafeFileWriter(File);
 
 impl SafeFileWriter {
     fn new(file: File) -> SafeFileWriter {

src/directory/mod.rs

@@ -13,7 +13,6 @@ mod managed_directory;
 mod ram_directory;
 mod read_only_source;
 mod watch_event_router;
-mod nrt_directory;
 
 /// Errors specific to the directory module.
 pub mod error;

src/directory/nrt_directory.rs

@@ -1,195 +0,0 @@
-use directory::Directory;
-use std::path::{PathBuf, Path};
-use directory::ReadOnlySource;
-use directory::error::OpenReadError;
-use directory::error::DeleteError;
-use std::io::{BufWriter, Cursor};
-use directory::SeekableWrite;
-use directory::error::OpenWriteError;
-use directory::WatchHandle;
-use directory::ram_directory::InnerRamDirectory;
-use std::sync::RwLock;
-use std::sync::Arc;
-use directory::WatchCallback;
-use std::fmt;
-use std::io;
-use std::io::{Seek, Write};
-use directory::DirectoryClone;
-
-
-const BUFFER_LEN: usize = 1_000_000;
-
-
-pub enum NRTWriter {
-    InRam {
-        buffer: Cursor<Vec<u8>>,
-        path: PathBuf,
-        nrt_directory: NRTDirectory
-    },
-    UnderlyingFile(BufWriter<Box<SeekableWrite>>)
-}
-
-impl NRTWriter {
-    pub fn new(path: PathBuf, nrt_directory: NRTDirectory) -> NRTWriter {
-        NRTWriter::InRam {
-            buffer: Cursor::new(Vec::with_capacity(BUFFER_LEN)),
-            path,
-            nrt_directory,
-        }
-    }
-}
-
-impl io::Seek for NRTWriter {
-    fn seek(&mut self, pos: io::SeekFrom) -> io::Result<u64> {
-        match self {
-            NRTWriter::InRam { buffer, path, nrt_directory } => {
-                buffer.seek(pos)
-            }
-            NRTWriter::UnderlyingFile(file) => {
-                file.seek(pos)
-            }
-        }
-    }
-}
-
-impl io::Write for NRTWriter {
-    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
-        self.write_all(buf)?;
-        Ok(buf.len())
-    }
-
-    fn flush(&mut self) -> io::Result<()> {
-        match self {
-            NRTWriter::InRam { buffer, path, nrt_directory } => {
-                let mut cache_wlock = nrt_directory.cache.write().unwrap();
-                cache_wlock.write(path.clone(), buffer.get_ref());
-                Ok(())
-            }
-            NRTWriter::UnderlyingFile(file) => {
-                file.flush()
-            }
-        }
-    }
-
-    fn write_all(&mut self, buf: &[u8]) -> io::Result<()> {
-        // Working around the borrow checker.
-        let mut underlying_write_opt: Option<BufWriter<Box<SeekableWrite>>> = None;
-        if let NRTWriter::InRam { buffer, path, nrt_directory } = self {
-            if buffer.get_ref().len() + buf.len() > BUFFER_LEN {
-                // We can't keep this in RAM. Let's move it to the underlying directory.
-                underlying_write_opt = Some(nrt_directory.open_write(path)
-                    .map_err(|open_err| {
-                        io::Error::new(io::ErrorKind::Other, open_err)
-                    })?);
-
-            }
-        }
-        if let Some(underlying_write) = underlying_write_opt {
-            *self = NRTWriter::UnderlyingFile(underlying_write);
-        }
-        match self {
-            NRTWriter::InRam { buffer, path, nrt_directory } => {
-                assert!(buffer.get_ref().len() + buf.len() <= BUFFER_LEN);
-                buffer.write_all(buf)
-            }
-            NRTWriter::UnderlyingFile(file) => {
-                file.write_all(buf)
-            }
-        }
-    }
-}
-
-pub struct NRTDirectory {
-    underlying: Box<Directory>,
-    cache: Arc<RwLock<InnerRamDirectory>>,
-}
-
-
-impl Clone for NRTDirectory {
-    fn clone(&self) -> Self {
-        NRTDirectory {
-            underlying: self.underlying.box_clone(),
-            cache: self.cache.clone()
-        }
-    }
-}
-
-impl NRTDirectory {
-    fn wrap(underlying: Box<Directory>) -> NRTDirectory {
-        NRTDirectory {
-            underlying,
-            cache: Default::default()
-        }
-    }
-}
-
-impl fmt::Debug for NRTDirectory {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        write!(f, "NRTDirectory({:?})", self.underlying)
-    }
-}
-
-impl Directory for NRTDirectory {
-    fn open_read(&self, path: &Path) -> Result<ReadOnlySource, OpenReadError> {
-        unimplemented!()
-    }
-
-    fn delete(&self, path: &Path) -> Result<(), DeleteError> {
-        // We explicitly release the lock, to prevent a panic on the underlying directory
-        // to poison the lock.
-        //
-        // File can only go from cache to underlying so the result does not lead to
-        // any inconsistency.
-        {
-            let mut cache_wlock = self.cache.write().unwrap();
-            if cache_wlock.exists(path) {
-                return cache_wlock.delete(path);
-            }
-        }
-        self.underlying.delete(path)
-    }
-
-    fn exists(&self, path: &Path) -> bool {
-        // We explicitly release the lock, to prevent a panic on the underlying directory
-        // to poison the lock.
-        //
-        // File can only go from cache to underlying so the result does not lead to
-        // any inconsistency.
-        {
-            let rlock_cache = self.cache.read().unwrap();
-            if rlock_cache.exists(path) {
-                return true;
-            }
-        }
-        self.underlying.exists(path)
-    }
-
-    fn open_write(&mut self, path: &Path) -> Result<BufWriter<Box<SeekableWrite>>, OpenWriteError> {
-        let mut cache_wlock = self.cache.write().unwrap();
-        // TODO might poison our lock. I don't know have a sound solution yet.
-        let path_buf = path.to_owned();
-        if self.underlying.exists(path) {
-            return Err(OpenWriteError::FileAlreadyExists(path_buf));
-        }
-        let exists = cache_wlock.write(path_buf.clone(), &[]);
-        // force the creation of the file to mimic the MMap directory.
-        if exists {
-            Err(OpenWriteError::FileAlreadyExists(path_buf))
-        } else {
-            let vec_writer = NRTWriter::new(path_buf.clone(), self.clone());
-            Ok(BufWriter::new(Box::new(vec_writer)))
-        }
-    }
-
-    fn atomic_read(&self, path: &Path) -> Result<Vec<u8>, OpenReadError> {
-        self.underlying.atomic_read(path)
-    }
-
-    fn atomic_write(&mut self, path: &Path, data: &[u8]) -> io::Result<()> {
-        self.underlying.atomic_write(path, data)
-    }
-
-    fn watch(&self, watch_callback: WatchCallback) -> WatchHandle {
-        self.underlying.watch(watch_callback)
-    }
-}

src/directory/ram_directory.rs

@@ -71,36 +71,36 @@ impl Write for VecWriter {
 }
 
 #[derive(Default)]
-pub(crate) struct InnerRamDirectory {
+struct InnerDirectory {
     fs: HashMap<PathBuf, ReadOnlySource>,
     watch_router: WatchCallbackList,
 }
 
-impl InnerRamDirectory {
+impl InnerDirectory {
-    pub fn write(&mut self, path: PathBuf, data: &[u8]) -> bool {
+    fn write(&mut self, path: PathBuf, data: &[u8]) -> bool {
         let data = ReadOnlySource::new(Vec::from(data));
         self.fs.insert(path, data).is_some()
     }
 
-    pub fn open_read(&self, path: &Path) -> Result<ReadOnlySource, OpenReadError> {
+    fn open_read(&self, path: &Path) -> Result<ReadOnlySource, OpenReadError> {
         self.fs
             .get(path)
             .ok_or_else(|| OpenReadError::FileDoesNotExist(PathBuf::from(path)))
-            .map(|el| el.clone())
+            .map(Clone::clone)
     }
 
-    pub fn delete(&mut self, path: &Path) -> result::Result<(), DeleteError> {
+    fn delete(&mut self, path: &Path) -> result::Result<(), DeleteError> {
         match self.fs.remove(path) {
             Some(_) => Ok(()),
             None => Err(DeleteError::FileDoesNotExist(PathBuf::from(path))),
         }
     }
 
-    pub fn exists(&self, path: &Path) -> bool {
+    fn exists(&self, path: &Path) -> bool {
         self.fs.contains_key(path)
     }
 
-    pub fn watch(&mut self, watch_handle: WatchCallback) -> WatchHandle {
+    fn watch(&mut self, watch_handle: WatchCallback) -> WatchHandle {
         self.watch_router.subscribe(watch_handle)
     }
 }
@@ -118,7 +118,7 @@ impl fmt::Debug for RAMDirectory {
 ///
 #[derive(Clone, Default)]
 pub struct RAMDirectory {
-    fs: Arc<RwLock<InnerRamDirectory>>,
+    fs: Arc<RwLock<InnerDirectory>>,
 }
 
 impl RAMDirectory {

src/docset.rs

@@ -1,4 +1,5 @@
 use common::BitSet;
+use fastfield::DeleteBitSet;
 use std::borrow::Borrow;
 use std::borrow::BorrowMut;
 use std::cmp::Ordering;
@@ -95,9 +96,23 @@ pub trait DocSet {
     }
 
     /// Returns the number documents matching.
-    ///
     /// Calling this method consumes the `DocSet`.
-    fn count(&mut self) -> u32 {
+    fn count(&mut self, delete_bitset: &DeleteBitSet) -> u32 {
+        let mut count = 0u32;
+        while self.advance() {
+            if !delete_bitset.is_deleted(self.doc()) {
+                count += 1u32;
+            }
+        }
+        count
+    }
+
+    /// Returns the count of documents, deleted or not.
+    /// Calling this method consumes the `DocSet`.
+    ///
+    /// Of course, the result is an upper bound of the result
+    /// given by `count()`.
+    fn count_including_deleted(&mut self) -> u32 {
         let mut count = 0u32;
         while self.advance() {
             count += 1u32;
@@ -127,13 +142,18 @@ impl<TDocSet: DocSet + ?Sized> DocSet for Box<TDocSet> {
         unboxed.size_hint()
     }
 
-    fn count(&mut self) -> u32 {
-        let unboxed: &mut TDocSet = self.borrow_mut();
-        unboxed.count()
-    }
-
     fn append_to_bitset(&mut self, bitset: &mut BitSet) {
         let unboxed: &mut TDocSet = self.borrow_mut();
         unboxed.append_to_bitset(bitset);
     }
+
+    fn count(&mut self, delete_bitset: &DeleteBitSet) -> u32 {
+        let unboxed: &mut TDocSet = self.borrow_mut();
+        unboxed.count(delete_bitset)
+    }
+
+    fn count_including_deleted(&mut self) -> u32 {
+        let unboxed: &mut TDocSet = self.borrow_mut();
+        unboxed.count_including_deleted()
+    }
 }

src/fastfield/bytes/mod.rs

@@ -23,14 +23,14 @@ mod tests {
         index_writer.add_document(doc!(field=>vec![0u8; 1000]));
         assert!(index_writer.commit().is_ok());
         let searcher = index.reader().unwrap().searcher();
-        let reader = searcher.segment_reader(0);
+        let segment_reader = searcher.segment_reader(0);
-        let bytes_reader = reader.bytes_fast_field_reader(field).unwrap();
+        let bytes_reader = segment_reader.fast_fields().bytes(field).unwrap();
 
-        assert_eq!(bytes_reader.get_val(0), &[0u8, 1, 2, 3]);
+        assert_eq!(bytes_reader.get_bytes(0), &[0u8, 1, 2, 3]);
-        assert!(bytes_reader.get_val(1).is_empty());
+        assert!(bytes_reader.get_bytes(1).is_empty());
-        assert_eq!(bytes_reader.get_val(2), &[255u8]);
+        assert_eq!(bytes_reader.get_bytes(2), &[255u8]);
-        assert_eq!(bytes_reader.get_val(3), &[1u8, 3, 5, 7, 9]);
+        assert_eq!(bytes_reader.get_bytes(3), &[1u8, 3, 5, 7, 9]);
         let long = vec![0u8; 1000];
-        assert_eq!(bytes_reader.get_val(4), long.as_slice());
+        assert_eq!(bytes_reader.get_bytes(4), long.as_slice());
     }
 }

src/fastfield/bytes/reader.rs

@@ -14,6 +14,7 @@ use DocId;
 ///
 /// Reading the value for a document is done by reading the start index for it,
 /// and the start index for the next document, and keeping the bytes in between.
+#[derive(Clone)]
 pub struct BytesFastFieldReader {
     idx_reader: FastFieldReader<u64>,
     values: OwningRef<ReadOnlySource, [u8]>,
@@ -28,10 +29,20 @@ impl BytesFastFieldReader {
         BytesFastFieldReader { idx_reader, values }
     }
 
-    /// Returns the bytes associated to the given `doc`
+    fn range(&self, doc: DocId) -> (usize, usize) {
-    pub fn get_val(&self, doc: DocId) -> &[u8] {
         let start = self.idx_reader.get(doc) as usize;
         let stop = self.idx_reader.get(doc + 1) as usize;
+        (start, stop)
+    }
+
+    /// Returns the bytes associated to the given `doc`
+    pub fn get_bytes(&self, doc: DocId) -> &[u8] {
+        let (start, stop) = self.range(doc);
         &self.values[start..stop]
     }
+
+    /// Returns the overall number of bytes in this bytes fast field.
+    pub fn total_num_bytes(&self) -> usize {
+        self.values.len()
+    }
 }

src/fastfield/delete.rs

@@ -53,16 +53,18 @@ impl DeleteBitSet {
         }
     }
 
-    /// Returns whether the document has been marked as deleted.
+    /// Returns true iff the document is still "alive". In other words, if it has not been deleted.
+    pub fn is_alive(&self, doc: DocId) -> bool {
+        !self.is_deleted(doc)
+    }
+
+    /// Returns true iff the document has been marked as deleted.
+    #[inline(always)]
     pub fn is_deleted(&self, doc: DocId) -> bool {
-        if self.len == 0 {
+        let byte_offset = doc / 8u32;
-            false
+        let b: u8 = (*self.data)[byte_offset as usize];
-        } else {
+        let shift = (doc & 7u32) as u8;
-            let byte_offset = doc / 8u32;
+        b & (1u8 << shift) != 0
-            let b: u8 = (*self.data)[byte_offset as usize];
-            let shift = (doc & 7u32) as u8;
-            b & (1u8 << shift) != 0
-        }
     }
 
     /// Summarize total space usage of this bitset.

src/fastfield/mod.rs

@@ -30,6 +30,7 @@ pub use self::error::{FastFieldNotAvailableError, Result};
 pub use self::facet_reader::FacetReader;
 pub use self::multivalued::{MultiValueIntFastFieldReader, MultiValueIntFastFieldWriter};
 pub use self::reader::FastFieldReader;
+pub use self::readers::FastFieldReaders;
 pub use self::serializer::FastFieldSerializer;
 pub use self::writer::{FastFieldsWriter, IntFastFieldWriter};
 use common;
@@ -43,6 +44,7 @@ mod error;
 mod facet_reader;
 mod multivalued;
 mod reader;
+mod readers;
 mod serializer;
 mod writer;
 
@@ -78,10 +80,6 @@ impl FastValue for u64 {
         *self
     }
 
-    fn as_u64(&self) -> u64 {
-        *self
-    }
-
     fn fast_field_cardinality(field_type: &FieldType) -> Option<Cardinality> {
         match *field_type {
             FieldType::U64(ref integer_options) => integer_options.get_fastfield_cardinality(),
@@ -89,6 +87,10 @@ impl FastValue for u64 {
             _ => None,
         }
     }
+
+    fn as_u64(&self) -> u64 {
+        *self
+    }
 }
 
 impl FastValue for i64 {

src/fastfield/multivalued/mod.rs

@@ -37,9 +37,7 @@ mod tests {
         let searcher = index.reader().unwrap().searcher();
         let segment_reader = searcher.segment_reader(0);
         let mut vals = Vec::new();
-        let multi_value_reader = segment_reader
+        let multi_value_reader = segment_reader.fast_fields().u64s(field).unwrap();
-            .multi_fast_field_reader::<u64>(field)
-            .unwrap();
         {
             multi_value_reader.get_vals(2, &mut vals);
             assert_eq!(&vals, &[4u64]);
@@ -198,9 +196,9 @@ mod tests {
         assert!(index_writer.commit().is_ok());
 
         let searcher = index.reader().unwrap().searcher();
-        let reader = searcher.segment_reader(0);
+        let segment_reader = searcher.segment_reader(0);
         let mut vals = Vec::new();
-        let multi_value_reader = reader.multi_fast_field_reader::<i64>(field).unwrap();
+        let multi_value_reader = segment_reader.fast_fields().i64s(field).unwrap();
         {
             multi_value_reader.get_vals(2, &mut vals);
             assert_eq!(&vals, &[-4i64]);

src/fastfield/multivalued/reader.rs

@@ -26,6 +26,13 @@ impl<Item: FastValue> MultiValueIntFastFieldReader<Item> {
         }
     }
 
+    pub(crate) fn into_u64s_reader(self) -> MultiValueIntFastFieldReader<u64> {
+        MultiValueIntFastFieldReader {
+            idx_reader: self.idx_reader,
+            vals_reader: self.vals_reader.into_u64_reader(),
+        }
+    }
+
     /// Returns `(start, stop)`, such that the values associated
     /// to the given document are `start..stop`.
     fn range(&self, doc: DocId) -> (u64, u64) {
@@ -41,13 +48,24 @@ impl<Item: FastValue> MultiValueIntFastFieldReader<Item> {
         vals.resize(len, Item::default());
         self.vals_reader.get_range_u64(start, &mut vals[..]);
     }
+
+    /// Returns the number of values associated with the document `DocId`.
+    pub fn num_vals(&self, doc: DocId) -> usize {
+        let (start, stop) = self.range(doc);
+        (stop - start) as usize
+    }
+
+    /// Returns the overall number of values in this field  .
+    pub fn total_num_vals(&self) -> u64 {
+        self.idx_reader.max_value()
+    }
 }
 
 #[cfg(test)]
 mod tests {
 
     use core::Index;
-    use schema::{Document, Facet, Schema};
+    use schema::{Facet, Schema};
 
     #[test]
     fn test_multifastfield_reader() {
@@ -58,22 +76,12 @@ mod tests {
         let mut index_writer = index
             .writer_with_num_threads(1, 30_000_000)
             .expect("Failed to create index writer.");
-        {
+        index_writer.add_document(doc!(
-            let mut doc = Document::new();
+            facet_field => Facet::from("/category/cat2"),
-            doc.add_facet(facet_field, "/category/cat2");
+            facet_field => Facet::from("/category/cat1"),
-            doc.add_facet(facet_field, "/category/cat1");
+        ));
-            index_writer.add_document(doc);
+        index_writer.add_document(doc!(facet_field => Facet::from("/category/cat2")));
-        }
+        index_writer.add_document(doc!(facet_field => Facet::from("/category/cat3")));
-        {
-            let mut doc = Document::new();
-            doc.add_facet(facet_field, "/category/cat2");
-            index_writer.add_document(doc);
-        }
-        {
-            let mut doc = Document::new();
-            doc.add_facet(facet_field, "/category/cat3");
-            index_writer.add_document(doc);
-        }
         index_writer.commit().expect("Commit failed");
         let searcher = index.reader().unwrap().searcher();
         let segment_reader = searcher.segment_reader(0);

src/fastfield/reader.rs

@@ -50,6 +50,15 @@ impl<Item: FastValue> FastFieldReader<Item> {
         }
     }
 
+    pub(crate) fn into_u64_reader(self) -> FastFieldReader<u64> {
+        FastFieldReader {
+            bit_unpacker: self.bit_unpacker,
+            min_value_u64: self.min_value_u64,
+            max_value_u64: self.max_value_u64,
+            _phantom: PhantomData,
+        }
+    }
+
     /// Return the value associated to the given document.
     ///
     /// This accessor should return as fast as possible.

src/fastfield/readers.rs

@@ -0,0 +1,191 @@
+use common::CompositeFile;
+use fastfield::BytesFastFieldReader;
+use fastfield::MultiValueIntFastFieldReader;
+use fastfield::{FastFieldNotAvailableError, FastFieldReader};
+use schema::{Cardinality, Field, FieldType, Schema};
+use space_usage::PerFieldSpaceUsage;
+use std::collections::HashMap;
+use Result;
+
+/// Provides access to all of the FastFieldReader.
+///
+/// Internally, `FastFieldReaders` have preloaded fast field readers,
+/// and just wraps several `HashMap`.
+pub struct FastFieldReaders {
+    fast_field_i64: HashMap<Field, FastFieldReader<i64>>,
+    fast_field_u64: HashMap<Field, FastFieldReader<u64>>,
+    fast_field_i64s: HashMap<Field, MultiValueIntFastFieldReader<i64>>,
+    fast_field_u64s: HashMap<Field, MultiValueIntFastFieldReader<u64>>,
+    fast_bytes: HashMap<Field, BytesFastFieldReader>,
+    fast_fields_composite: CompositeFile,
+}
+
+enum FastType {
+    I64,
+    U64,
+}
+
+fn type_and_cardinality(field_type: &FieldType) -> Option<(FastType, Cardinality)> {
+    match field_type {
+        FieldType::U64(options) => options
+            .get_fastfield_cardinality()
+            .map(|cardinality| (FastType::U64, cardinality)),
+        FieldType::I64(options) => options
+            .get_fastfield_cardinality()
+            .map(|cardinality| (FastType::I64, cardinality)),
+        FieldType::HierarchicalFacet => Some((FastType::U64, Cardinality::MultiValues)),
+        _ => None,
+    }
+}
+
+impl FastFieldReaders {
+    pub(crate) fn load_all(
+        schema: &Schema,
+        fast_fields_composite: &CompositeFile,
+    ) -> Result<FastFieldReaders> {
+        let mut fast_field_readers = FastFieldReaders {
+            fast_field_i64: Default::default(),
+            fast_field_u64: Default::default(),
+            fast_field_i64s: Default::default(),
+            fast_field_u64s: Default::default(),
+            fast_bytes: Default::default(),
+            fast_fields_composite: fast_fields_composite.clone(),
+        };
+        for (field_id, field_entry) in schema.fields().iter().enumerate() {
+            let field = Field(field_id as u32);
+            let field_type = field_entry.field_type();
+            if field_type == &FieldType::Bytes {
+                let idx_reader = fast_fields_composite
+                    .open_read_with_idx(field, 0)
+                    .ok_or_else(|| FastFieldNotAvailableError::new(field_entry))
+                    .map(FastFieldReader::open)?;
+                let data = fast_fields_composite
+                    .open_read_with_idx(field, 1)
+                    .ok_or_else(|| FastFieldNotAvailableError::new(field_entry))?;
+                fast_field_readers
+                    .fast_bytes
+                    .insert(field, BytesFastFieldReader::open(idx_reader, data));
+            } else if let Some((fast_type, cardinality)) = type_and_cardinality(field_type) {
+                match cardinality {
+                    Cardinality::SingleValue => {
+                        if let Some(fast_field_data) = fast_fields_composite.open_read(field) {
+                            match fast_type {
+                                FastType::U64 => {
+                                    let fast_field_reader = FastFieldReader::open(fast_field_data);
+                                    fast_field_readers
+                                        .fast_field_u64
+                                        .insert(field, fast_field_reader);
+                                }
+                                FastType::I64 => {
+                                    fast_field_readers.fast_field_i64.insert(
+                                        field,
+                                        FastFieldReader::open(fast_field_data.clone()),
+                                    );
+                                }
+                            }
+                        } else {
+                            return Err(From::from(FastFieldNotAvailableError::new(field_entry)));
+                        }
+                    }
+                    Cardinality::MultiValues => {
+                        let idx_opt = fast_fields_composite.open_read_with_idx(field, 0);
+                        let data_opt = fast_fields_composite.open_read_with_idx(field, 1);
+                        if let (Some(fast_field_idx), Some(fast_field_data)) = (idx_opt, data_opt) {
+                            let idx_reader = FastFieldReader::open(fast_field_idx);
+                            match fast_type {
+                                FastType::I64 => {
+                                    let vals_reader = FastFieldReader::open(fast_field_data);
+                                    let multivalued_int_fast_field =
+                                        MultiValueIntFastFieldReader::open(idx_reader, vals_reader);
+                                    fast_field_readers
+                                        .fast_field_i64s
+                                        .insert(field, multivalued_int_fast_field);
+                                }
+                                FastType::U64 => {
+                                    let vals_reader = FastFieldReader::open(fast_field_data);
+                                    let multivalued_int_fast_field =
+                                        MultiValueIntFastFieldReader::open(idx_reader, vals_reader);
+                                    fast_field_readers
+                                        .fast_field_u64s
+                                        .insert(field, multivalued_int_fast_field);
+                                }
+                            }
+                        } else {
+                            return Err(From::from(FastFieldNotAvailableError::new(field_entry)));
+                        }
+                    }
+                }
+            }
+        }
+        Ok(fast_field_readers)
+    }
+
+    pub(crate) fn space_usage(&self) -> PerFieldSpaceUsage {
+        self.fast_fields_composite.space_usage()
+    }
+
+    /// Returns the `u64` fast field reader reader associated to `field`.
+    ///
+    /// If `field` is not a u64 fast field, this method returns `None`.
+    pub fn u64(&self, field: Field) -> Option<FastFieldReader<u64>> {
+        self.fast_field_u64.get(&field).cloned()
+    }
+
+    /// If the field is a u64-fast field return the associated reader.
+    /// If the field is a i64-fast field, return the associated u64 reader. Values are
+    /// mapped from i64 to u64 using a (well the, it is unique) monotonic mapping.    ///
+    ///
+    /// This method is useful when merging segment reader.
+    pub(crate) fn u64_lenient(&self, field: Field) -> Option<FastFieldReader<u64>> {
+        if let Some(u64_ff_reader) = self.u64(field) {
+            return Some(u64_ff_reader);
+        }
+        if let Some(i64_ff_reader) = self.i64(field) {
+            return Some(i64_ff_reader.into_u64_reader());
+        }
+        None
+    }
+
+    /// Returns the `i64` fast field reader reader associated to `field`.
+    ///
+    /// If `field` is not a i64 fast field, this method returns `None`.
+    pub fn i64(&self, field: Field) -> Option<FastFieldReader<i64>> {
+        self.fast_field_i64.get(&field).cloned()
+    }
+
+    /// Returns a `u64s` multi-valued fast field reader reader associated to `field`.
+    ///
+    /// If `field` is not a u64 multi-valued fast field, this method returns `None`.
+    pub fn u64s(&self, field: Field) -> Option<MultiValueIntFastFieldReader<u64>> {
+        self.fast_field_u64s.get(&field).cloned()
+    }
+
+    /// If the field is a u64s-fast field return the associated reader.
+    /// If the field is a i64s-fast field, return the associated u64s reader. Values are
+    /// mapped from i64 to u64 using a (well the, it is unique) monotonic mapping.
+    ///
+    /// This method is useful when merging segment reader.
+    pub(crate) fn u64s_lenient(&self, field: Field) -> Option<MultiValueIntFastFieldReader<u64>> {
+        if let Some(u64s_ff_reader) = self.u64s(field) {
+            return Some(u64s_ff_reader);
+        }
+        if let Some(i64s_ff_reader) = self.i64s(field) {
+            return Some(i64s_ff_reader.into_u64s_reader());
+        }
+        None
+    }
+
+    /// Returns a `i64s` multi-valued fast field reader reader associated to `field`.
+    ///
+    /// If `field` is not a i64 multi-valued fast field, this method returns `None`.
+    pub fn i64s(&self, field: Field) -> Option<MultiValueIntFastFieldReader<i64>> {
+        self.fast_field_i64s.get(&field).cloned()
+    }
+
+    /// Returns the `bytes` fast field reader associated to `field`.
+    ///
+    /// If `field` is not a bytes fast field, returns `None`.
+    pub fn bytes(&self, field: Field) -> Option<BytesFastFieldReader> {
+        self.fast_bytes.get(&field).cloned()
+    }
+}

src/indexer/delete_queue.rs

@@ -179,11 +179,6 @@ pub struct DeleteCursor {
 }
 
 impl DeleteCursor {
-
-    pub fn empty() -> DeleteCursor {
-        DeleteQueue::new().cursor()
-    }
-
     /// Skips operations and position it so that
     /// - either all of the delete operation currently in the
     ///   queue are consume and the next get will return None.

src/indexer/index_writer.rs

@@ -259,7 +259,7 @@ pub fn advance_deletes(
             write_delete_bitset(&delete_bitset, &mut delete_file)?;
         }
     }
-    segment_entry.set_meta(target_opstamp, segment.meta().clone());
+    segment_entry.set_meta(segment.meta().clone());
     Ok(())
 }
 
@@ -326,12 +326,7 @@ fn index_documents(
         // to even open the segment.
         None
     };
-    let segment_entry = SegmentEntry::new(
+    let segment_entry = SegmentEntry::new(segment_meta, delete_cursor, delete_bitset_opt);
-        segment_meta,
-        delete_cursor,
-        delete_bitset_opt,
-        last_docstamp,
-    );
     Ok(segment_updater.add_segment(generation, segment_entry))
 }
 
@@ -366,9 +361,9 @@ impl IndexWriter {
     }
 
     #[doc(hidden)]
-    pub fn add_segment(&mut self, segment_meta: SegmentMeta, opstamp: u64) {
+    pub fn add_segment(&mut self, segment_meta: SegmentMeta) {
         let delete_cursor = self.delete_queue.cursor();
-        let segment_entry = SegmentEntry::new(segment_meta, delete_cursor, None, opstamp);
+        let segment_entry = SegmentEntry::new(segment_meta, delete_cursor, None);
         self.segment_updater
             .add_segment(self.generation, segment_entry);
     }
@@ -532,7 +527,7 @@ impl IndexWriter {
         //
         // This will reach an end as the only document_sender
         // was dropped with the index_writer.
-        for _ in document_receiver.iter() {}
+        for _ in document_receiver.clone() {}
 
         Ok(())
     }
@@ -559,16 +554,6 @@ impl IndexWriter {
     /// using this API.
     /// See [`PreparedCommit::set_payload()`](PreparedCommit.html)
     pub fn prepare_commit(&mut self) -> Result<PreparedCommit> {
-        info!("Preparing commit");
-        self.prepare_commit_internal(false)
-    }
-
-    pub fn prepare_commit_soft(&mut self) -> Result<PreparedCommit> {
-        info!("Preparing soft commit");
-        self.prepare_commit_internal(true)
-    }
-
-    pub(crate) fn prepare_commit_internal(&mut self, soft: bool) -> Result<PreparedCommit> {
         // Here, because we join all of the worker threads,
         // all of the segment update for this commit have been
         // sent.
@@ -591,13 +576,13 @@ impl IndexWriter {
             let indexing_worker_result = worker_handle
                 .join()
                 .map_err(|e| TantivyError::ErrorInThread(format!("{:?}", e)))?;
-            // add a new worker for the next generation, whether the worker failed or not.
-            self.add_indexing_worker()?;
             indexing_worker_result?;
+            // add a new worker for the next generation.
+            self.add_indexing_worker()?;
         }
 
         let commit_opstamp = self.stamper.stamp();
-        let prepared_commit = PreparedCommit::new(self, commit_opstamp, soft);
+        let prepared_commit = PreparedCommit::new(self, commit_opstamp);
         info!("Prepared commit {}", commit_opstamp);
         Ok(prepared_commit)
     }
@@ -620,11 +605,6 @@ impl IndexWriter {
         self.prepare_commit()?.commit()
     }
 
-
-    pub fn soft_commit(&mut self) -> Result<u64> {
-        self.prepare_commit_soft()?.commit()
-    }
-
     pub(crate) fn segment_updater(&self) -> &SegmentUpdater {
         &self.segment_updater
     }
@@ -752,7 +732,6 @@ mod tests {
     use Index;
     use ReloadPolicy;
     use Term;
-    use IndexReader;
 
     #[test]
     fn test_operations_group() {
@@ -886,13 +865,6 @@ mod tests {
         let _index_writer_two = index.writer(3_000_000).unwrap();
     }
 
-    fn num_docs_containing_text(reader: &IndexReader, term: &str) -> u64 {
-        let searcher = reader.searcher();
-        let text_field = reader.schema().get_field("text").unwrap();
-        let term = Term::from_field_text(text_field, term);
-        searcher.doc_freq(&term)
-    }
-
     #[test]
     fn test_commit_and_rollback() {
         let mut schema_builder = schema::Schema::builder();
@@ -909,12 +881,9 @@ mod tests {
             searcher.doc_freq(&term)
         };
 
-        let mut index_writer = index.writer(3_000_000).unwrap();
-
-        assert_eq!(index_writer.commit_opstamp(), 0u64);
-        assert_eq!(num_docs_containing_text(&reader, "a"), 0);
         {
             // writing the segment
+            let mut index_writer = index.writer(3_000_000).unwrap();
             index_writer.add_document(doc!(text_field=>"a"));
             index_writer.rollback().unwrap();
             assert_eq!(index_writer.commit_opstamp(), 0u64);
@@ -933,35 +902,6 @@ mod tests {
         reader.searcher();
     }
 
-    #[test]
-    fn test_softcommit_and_rollback() {
-        let mut schema_builder = schema::Schema::builder();
-        let text_field = schema_builder.add_text_field("text", schema::TEXT);
-        let index = Index::create_in_ram(schema_builder.build());
-        let reader = index.reader().unwrap();
-        // writing the segment
-        let mut index_writer = index.writer(3_000_000).unwrap();
-        index_writer.add_document(doc!(text_field=>"a"));
-        index_writer.rollback().unwrap();
-
-        assert_eq!(index_writer.commit_opstamp(), 0u64);
-        assert_eq!(num_docs_containing_text(&reader, "a"), 0u64);
-        {
-            index_writer.add_document(doc!(text_field=>"b"));
-            index_writer.add_document(doc!(text_field=>"c"));
-        }
-        assert!(index_writer.soft_commit().is_ok());
-        reader.reload().unwrap(); // we need to load soft committed stuff.
-        assert_eq!(num_docs_containing_text(&reader, "a"), 0u64);
-        assert_eq!(num_docs_containing_text(&reader, "b"), 1u64);
-        assert_eq!(num_docs_containing_text(&reader, "c"), 1u64);
-        index_writer.rollback().unwrap();
-        reader.reload().unwrap();
-        assert_eq!(num_docs_containing_text(&reader, "a"), 0u64);
-        assert_eq!(num_docs_containing_text(&reader, "b"), 0u64);
-        assert_eq!(num_docs_containing_text(&reader, "c"), 0u64);
-    }
-
     #[test]
     fn test_with_merges() {
         let mut schema_builder = schema::Schema::builder();
@@ -995,7 +935,7 @@ mod tests {
 
             reader.reload().unwrap();
 
-            assert_eq!(num_docs_containing_text(&reader, "a"), 200);
+            assert_eq!(num_docs_containing("a"), 200);
             assert!(index.searchable_segments().unwrap().len() < 8);
         }
     }
@@ -1038,7 +978,7 @@ mod tests {
         let mut schema_builder = schema::Schema::builder();
         let text_field = schema_builder.add_text_field("text", schema::TEXT);
         let index = Index::create_in_ram(schema_builder.build());
-        let reader = index.reader();
+
         {
             // writing the segment
             let mut index_writer = index.writer_with_num_threads(4, 12_000_000).unwrap();

src/indexer/log_merge_policy.rs

@@ -52,7 +52,7 @@ impl MergePolicy for LogMergePolicy {
 
         let mut size_sorted_tuples = segments
             .iter()
-            .map(|x| x.num_docs())
+            .map(SegmentMeta::num_docs)
             .enumerate()
             .collect::<Vec<(usize, u32)>>();
 

src/indexer/merger.rs

@@ -3,6 +3,7 @@ use core::Segment;
 use core::SegmentReader;
 use core::SerializableSegment;
 use docset::DocSet;
+use fastfield::BytesFastFieldReader;
 use fastfield::DeleteBitSet;
 use fastfield::FastFieldReader;
 use fastfield::FastFieldSerializer;
@@ -72,7 +73,7 @@ fn compute_min_max_val(
                 // some deleted documents,
                 // we need to recompute the max / min
                 (0..max_doc)
-                    .filter(|doc_id| !delete_bitset.is_deleted(*doc_id))
+                    .filter(|doc_id| delete_bitset.is_alive(*doc_id))
                     .map(|doc_id| u64_reader.get(doc_id))
                     .minmax()
                     .into_option()
@@ -239,7 +240,10 @@ impl IndexMerger {
         let mut max_value = u64::min_value();
 
         for reader in &self.readers {
-            let u64_reader: FastFieldReader<u64> = reader.fast_field_reader(field)?;
+            let u64_reader: FastFieldReader<u64> = reader
+                .fast_fields()
+                .u64_lenient(field)
+                .expect("Failed to find a reader for single fast field. This is a tantivy bug and it should never happen.");
             if let Some((seg_min_val, seg_max_val)) =
                 compute_min_max_val(&u64_reader, reader.max_doc(), reader.delete_bitset())
             {
@@ -282,24 +286,28 @@ impl IndexMerger {
         fast_field_serializer: &mut FastFieldSerializer,
     ) -> Result<()> {
         let mut total_num_vals = 0u64;
+        let mut u64s_readers: Vec<MultiValueIntFastFieldReader<u64>> = Vec::new();
 
         // In the first pass, we compute the total number of vals.
         //
         // This is required by the bitpacker, as it needs to know
         // what should be the bit length use for bitpacking.
         for reader in &self.readers {
-            let idx_reader = reader.fast_field_reader_with_idx::<u64>(field, 0)?;
+            let u64s_reader = reader.fast_fields()
+                .u64s_lenient(field)
+                .expect("Failed to find index for multivalued field. This is a bug in tantivy, please report.");
+
             if let Some(delete_bitset) = reader.delete_bitset() {
                 for doc in 0u32..reader.max_doc() {
-                    if !delete_bitset.is_deleted(doc) {
+                    if delete_bitset.is_alive(doc) {
-                        let start = idx_reader.get(doc);
+                        let num_vals = u64s_reader.num_vals(doc) as u64;
-                        let end = idx_reader.get(doc + 1);
+                        total_num_vals += num_vals;
-                        total_num_vals += end - start;
                     }
                 }
             } else {
-                total_num_vals += idx_reader.max_value();
+                total_num_vals += u64s_reader.total_num_vals();
             }
+            u64s_readers.push(u64s_reader);
         }
 
         // We can now create our `idx` serializer, and in a second pass,
@@ -307,13 +315,10 @@ impl IndexMerger {
         let mut serialize_idx =
             fast_field_serializer.new_u64_fast_field_with_idx(field, 0, total_num_vals, 0)?;
         let mut idx = 0;
-        for reader in &self.readers {
+        for (segment_reader, u64s_reader) in self.readers.iter().zip(&u64s_readers) {
-            let idx_reader = reader.fast_field_reader_with_idx::<u64>(field, 0)?;
+            for doc in segment_reader.doc_ids_alive() {
-            for doc in reader.doc_ids_alive() {
                 serialize_idx.add_val(idx)?;
-                let start = idx_reader.get(doc);
+                idx += u64s_reader.num_vals(doc) as u64;
-                let end = idx_reader.get(doc + 1);
-                idx += end - start;
             }
         }
         serialize_idx.add_val(idx)?;
@@ -344,8 +349,10 @@ impl IndexMerger {
             for (segment_ord, segment_reader) in self.readers.iter().enumerate() {
                 let term_ordinal_mapping: &[TermOrdinal] =
                     term_ordinal_mappings.get_segment(segment_ord);
-                let ff_reader: MultiValueIntFastFieldReader<u64> =
+                let ff_reader: MultiValueIntFastFieldReader<u64> = segment_reader
-                    segment_reader.multi_fast_field_reader(field)?;
+                    .fast_fields()
+                    .u64s(field)
+                    .expect("Could not find multivalued u64 fast value reader.");
                 // TODO optimize if no deletes
                 for doc in segment_reader.doc_ids_alive() {
                     ff_reader.get_vals(doc, &mut vals);
@@ -377,6 +384,8 @@ impl IndexMerger {
 
         let mut vals = Vec::with_capacity(100);
 
+        let mut ff_readers = Vec::new();
+
         // Our values are bitpacked and we need to know what should be
         // our bitwidth and our minimum value before serializing any values.
         //
@@ -385,7 +394,10 @@ impl IndexMerger {
         // maximum value and initialize our Serializer.
         for reader in &self.readers {
             let ff_reader: MultiValueIntFastFieldReader<u64> =
-                reader.multi_fast_field_reader(field)?;
+                reader.fast_fields().u64s_lenient(field).expect(
+                    "Failed to find multivalued fast field reader. This is a bug in \
+                     tantivy. Please report.",
+                );
             for doc in reader.doc_ids_alive() {
                 ff_reader.get_vals(doc, &mut vals);
                 for &val in &vals {
@@ -393,6 +405,7 @@ impl IndexMerger {
                     max_value = cmp::max(val, max_value);
                 }
             }
+            ff_readers.push(ff_reader);
             // TODO optimize when no deletes
         }
 
@@ -405,9 +418,7 @@ impl IndexMerger {
         {
             let mut serialize_vals = fast_field_serializer
                 .new_u64_fast_field_with_idx(field, min_value, max_value, 1)?;
-            for reader in &self.readers {
+            for (reader, ff_reader) in self.readers.iter().zip(ff_readers) {
-                let ff_reader: MultiValueIntFastFieldReader<u64> =
-                    reader.multi_fast_field_reader(field)?;
                 // TODO optimize if no deletes
                 for doc in reader.doc_ids_alive() {
                     ff_reader.get_vals(doc, &mut vals);
@@ -426,19 +437,53 @@ impl IndexMerger {
         field: Field,
         fast_field_serializer: &mut FastFieldSerializer,
     ) -> Result<()> {
-        self.write_fast_field_idx(field, fast_field_serializer)?;
+        let mut total_num_vals = 0u64;
+        let mut bytes_readers: Vec<BytesFastFieldReader> = Vec::new();
+
+        for reader in &self.readers {
+            let bytes_reader = reader.fast_fields().bytes(field).expect(
+                "Failed to find bytes fast field reader. This is a bug in tantivy, please report.",
+            );
+            if let Some(delete_bitset) = reader.delete_bitset() {
+                for doc in 0u32..reader.max_doc() {
+                    if delete_bitset.is_alive(doc) {
+                        let num_vals = bytes_reader.get_bytes(doc).len() as u64;
+                        total_num_vals += num_vals;
+                    }
+                }
+            } else {
+                total_num_vals += bytes_reader.total_num_bytes() as u64;
+            }
+            bytes_readers.push(bytes_reader);
+        }
+
+        {
+            // We can now create our `idx` serializer, and in a second pass,
+            // can effectively push the different indexes.
+            let mut serialize_idx =
+                fast_field_serializer.new_u64_fast_field_with_idx(field, 0, total_num_vals, 0)?;
+            let mut idx = 0;
+            for (segment_reader, bytes_reader) in self.readers.iter().zip(&bytes_readers) {
+                for doc in segment_reader.doc_ids_alive() {
+                    serialize_idx.add_val(idx)?;
+                    idx += bytes_reader.get_bytes(doc).len() as u64;
+                }
+            }
+            serialize_idx.add_val(idx)?;
+            serialize_idx.close_field()?;
+        }
 
         let mut serialize_vals = fast_field_serializer.new_bytes_fast_field_with_idx(field, 1)?;
-        for reader in &self.readers {
+        for segment_reader in &self.readers {
-            let bytes_reader = reader.bytes_fast_field_reader(field)?;
+            let bytes_reader = segment_reader.fast_fields().bytes(field)
+                .expect("Failed to find bytes field in fast field reader. This is a bug in tantivy. Please report.");
             // TODO: optimize if no deletes
-            for doc in reader.doc_ids_alive() {
+            for doc in segment_reader.doc_ids_alive() {
-                let val = bytes_reader.get_val(doc);
+                let val = bytes_reader.get_bytes(doc);
                 serialize_vals.write_all(val)?;
             }
         }
         serialize_vals.flush()?;
-
         Ok(())
     }
 
@@ -979,14 +1024,16 @@ mod tests {
 
             let score_field_reader = searcher
                 .segment_reader(0)
-                .fast_field_reader::<u64>(score_field)
+                .fast_fields()
+                .u64(score_field)
                 .unwrap();
             assert_eq!(score_field_reader.min_value(), 4000);
             assert_eq!(score_field_reader.max_value(), 7000);
 
             let score_field_reader = searcher
                 .segment_reader(1)
-                .fast_field_reader::<u64>(score_field)
+                .fast_fields()
+                .u64(score_field)
                 .unwrap();
             assert_eq!(score_field_reader.min_value(), 1);
             assert_eq!(score_field_reader.max_value(), 3);
@@ -1037,7 +1084,8 @@ mod tests {
             );
             let score_field_reader = searcher
                 .segment_reader(0)
-                .fast_field_reader::<u64>(score_field)
+                .fast_fields()
+                .u64(score_field)
                 .unwrap();
             assert_eq!(score_field_reader.min_value(), 3);
             assert_eq!(score_field_reader.max_value(), 7000);
@@ -1083,7 +1131,8 @@ mod tests {
             );
             let score_field_reader = searcher
                 .segment_reader(0)
-                .fast_field_reader::<u64>(score_field)
+                .fast_fields()
+                .u64(score_field)
                 .unwrap();
             assert_eq!(score_field_reader.min_value(), 3);
             assert_eq!(score_field_reader.max_value(), 7000);
@@ -1135,7 +1184,8 @@ mod tests {
             );
             let score_field_reader = searcher
                 .segment_reader(0)
-                .fast_field_reader::<u64>(score_field)
+                .fast_fields()
+                .u64(score_field)
                 .unwrap();
             assert_eq!(score_field_reader.min_value(), 6000);
             assert_eq!(score_field_reader.max_value(), 7000);
@@ -1381,7 +1431,7 @@ mod tests {
 
         {
             let segment = searcher.segment_reader(0u32);
-            let ff_reader = segment.multi_fast_field_reader(int_field).unwrap();
+            let ff_reader = segment.fast_fields().u64s(int_field).unwrap();
 
             ff_reader.get_vals(0, &mut vals);
             assert_eq!(&vals, &[1, 2]);
@@ -1416,7 +1466,7 @@ mod tests {
 
         {
             let segment = searcher.segment_reader(1u32);
-            let ff_reader = segment.multi_fast_field_reader(int_field).unwrap();
+            let ff_reader = segment.fast_fields().u64s(int_field).unwrap();
             ff_reader.get_vals(0, &mut vals);
             assert_eq!(&vals, &[28, 27]);
 
@@ -1426,7 +1476,7 @@ mod tests {
 
         {
             let segment = searcher.segment_reader(2u32);
-            let ff_reader = segment.multi_fast_field_reader(int_field).unwrap();
+            let ff_reader = segment.fast_fields().u64s(int_field).unwrap();
             ff_reader.get_vals(0, &mut vals);
             assert_eq!(&vals, &[20]);
         }
@@ -1459,7 +1509,7 @@ mod tests {
                     .collect::<Vec<_>>()
             );
             let segment = searcher.segment_reader(0u32);
-            let ff_reader = segment.multi_fast_field_reader(int_field).unwrap();
+            let ff_reader = segment.fast_fields().u64s(int_field).unwrap();
 
             ff_reader.get_vals(0, &mut vals);
             assert_eq!(&vals, &[1, 2]);

src/indexer/prepared_commit.rs

@@ -6,20 +6,14 @@ pub struct PreparedCommit<'a> {
     index_writer: &'a mut IndexWriter,
     payload: Option<String>,
     opstamp: u64,
-    soft: bool,
 }
 
 impl<'a> PreparedCommit<'a> {
-    pub(crate) fn new(
+    pub(crate) fn new(index_writer: &'a mut IndexWriter, opstamp: u64) -> PreparedCommit {
-        index_writer: &'a mut IndexWriter,
-        opstamp: u64,
-        soft: bool,
-    ) -> PreparedCommit {
         PreparedCommit {
             index_writer,
             payload: None,
             opstamp,
-            soft,
         }
     }
 
@@ -39,7 +33,7 @@ impl<'a> PreparedCommit<'a> {
         info!("committing {}", self.opstamp);
         self.index_writer
             .segment_updater()
-            .commit(self.opstamp, self.payload, self.soft)?;
+            .commit(self.opstamp, self.payload)?;
         Ok(self.opstamp)
     }
 }

src/indexer/segment_entry.rs

@@ -22,7 +22,6 @@ pub struct SegmentEntry {
     meta: SegmentMeta,
     delete_bitset: Option<BitSet>,
     delete_cursor: DeleteCursor,
-    opstamp: u64,
 }
 
 impl SegmentEntry {
@@ -31,20 +30,14 @@ impl SegmentEntry {
         segment_meta: SegmentMeta,
         delete_cursor: DeleteCursor,
         delete_bitset: Option<BitSet>,
-        opstamp: u64,
     ) -> SegmentEntry {
         SegmentEntry {
             meta: segment_meta,
             delete_bitset,
             delete_cursor,
-            opstamp,
         }
     }
 
-    pub fn opstamp(&self) -> u64 {
-        self.opstamp
-    }
-
     /// Return a reference to the segment entry deleted bitset.
     ///
     /// `DocId` in this bitset are flagged as deleted.
@@ -53,8 +46,7 @@ impl SegmentEntry {
     }
 
     /// Set the `SegmentMeta` for this segment.
-    pub fn set_meta(&mut self, opstamp: u64, segment_meta: SegmentMeta) {
+    pub fn set_meta(&mut self, segment_meta: SegmentMeta) {
-        self.opstamp = opstamp;
         self.meta = segment_meta;
     }
 

src/indexer/segment_manager.rs

@@ -11,47 +11,11 @@ use std::path::PathBuf;
 use std::sync::RwLock;
 use std::sync::{RwLockReadGuard, RwLockWriteGuard};
 use Result as TantivyResult;
-use std::sync::Arc;
-use std::collections::HashMap;
-
-/// Provides a read-only view of the available segments.
-#[derive(Clone)]
-pub struct AvailableSegments {
-    registers: Arc<RwLock<SegmentRegisters>>,
-}
-
-impl AvailableSegments {
-    pub fn committed(&self) -> Vec<SegmentMeta> {
-        self.registers
-            .read()
-            .unwrap()
-            .committed
-            .segment_metas()
-    }
-
-    pub fn soft_committed(&self) -> Vec<SegmentMeta> {
-        self.registers
-            .read()
-            .unwrap()
-            .soft_committed
-            .segment_metas()
-    }
-}
-
 
+#[derive(Default)]
 struct SegmentRegisters {
-    uncommitted: HashMap<SegmentId, SegmentEntry>,
+    uncommitted: SegmentRegister,
     committed: SegmentRegister,
-    /// soft commits can advance committed segment to a future delete
-    /// opstamp.
-    ///
-    /// In that case the same `SegmentId` can appear in both `committed`
-    /// and in `committed_in_the_future`.
-    ///
-    /// We do not consider these segments for merges.
-    soft_committed: SegmentRegister,
-    /// `DeleteCursor`, positionned on the soft commit.
-    delete_cursor: DeleteCursor,
 }
 
 /// The segment manager stores the list of segments
@@ -59,8 +23,9 @@ struct SegmentRegisters {
 ///
 /// It guarantees the atomicity of the
 /// changes (merges especially)
+#[derive(Default)]
 pub struct SegmentManager {
-    registers: Arc<RwLock<SegmentRegisters>>
+    registers: RwLock<SegmentRegisters>,
 }
 
 impl Debug for SegmentManager {
@@ -81,17 +46,11 @@ pub fn get_mergeable_segments(
     let registers_lock = segment_manager.read();
     (
         registers_lock
-            .soft_committed
+            .committed
             .get_mergeable_segments(in_merge_segment_ids),
         registers_lock
             .uncommitted
-            .values()
+            .get_mergeable_segments(in_merge_segment_ids),
-            .map(|segment_entry| segment_entry.meta())
-            .filter(|segment_meta| {
-                !in_merge_segment_ids.contains(&segment_meta.id())
-            })
-            .cloned()
-            .collect::<Vec<_>>()
     )
 }
 
@@ -99,22 +58,21 @@ impl SegmentManager {
     pub fn from_segments(
         segment_metas: Vec<SegmentMeta>,
         delete_cursor: &DeleteCursor,
-        opstamp: u64,
     ) -> SegmentManager {
         SegmentManager {
-            registers: Arc::new(RwLock::new(SegmentRegisters {
+            registers: RwLock::new(SegmentRegisters {
-                uncommitted: HashMap::default(),
+                uncommitted: SegmentRegister::default(),
-                committed: SegmentRegister::new(segment_metas.clone(), opstamp),
+                committed: SegmentRegister::new(segment_metas, delete_cursor),
-                soft_committed: SegmentRegister::new(segment_metas, opstamp),
+            }),
-                delete_cursor: delete_cursor.clone(),
-            }))
         }
     }
 
-    pub fn available_segments_view(&self) -> AvailableSegments {
+    /// Returns all of the segment entries (committed or uncommitted)
-        AvailableSegments {
+    pub fn segment_entries(&self) -> Vec<SegmentEntry> {
-            registers: self.registers.clone()
+        let registers_lock = self.read();
-        }
+        let mut segment_entries = registers_lock.uncommitted.segment_entries();
+        segment_entries.extend(registers_lock.committed.segment_entries());
+        segment_entries
     }
 
     /// List the files that are useful to the index.
@@ -150,76 +108,44 @@ impl SegmentManager {
         let mut registers_lock = self.write();
         registers_lock
             .committed
-            .segment_metas()
+            .segment_entries()
             .iter()
-            .filter(|segment_meta| segment_meta.num_docs() == 0)
+            .filter(|segment| segment.meta().num_docs() == 0)
-            .for_each(|segment_meta| {
+            .for_each(|segment| {
                 registers_lock
                     .committed
-                    .remove_segment(&segment_meta.id())
+                    .remove_segment(&segment.segment_id())
-            });
-        registers_lock
-            .soft_committed
-            .segment_metas()
-            .iter()
-            .filter(|segment_meta| segment_meta.num_docs() == 0)
-            .for_each(|segment_meta| {
-                registers_lock
-                    .committed
-                    .remove_segment(&segment_meta.id())
             });
     }
 
-    /// Returns all of the segment entries (soft committed or uncommitted)
+    pub fn commit(&self, segment_entries: Vec<SegmentEntry>) {
-    pub fn segment_entries(&self) -> Vec<SegmentEntry> {
-        let registers_lock = self.read();
-        let mut segment_entries: Vec<SegmentEntry   > = registers_lock.uncommitted.values().cloned().collect();
-        segment_entries.extend(registers_lock.soft_committed.segment_entries(&registers_lock.delete_cursor).into_iter());
-        segment_entries
-    }
-
-
-    pub fn commit(&self, opstamp: u64, segment_entries: Vec<SegmentEntry>) {
         let mut registers_lock = self.write();
+        registers_lock.committed.clear();
         registers_lock.uncommitted.clear();
-        registers_lock
+        for segment_entry in segment_entries {
-            .committed
+            registers_lock.committed.add_segment_entry(segment_entry);
-            .set_commit(opstamp, segment_entries.clone());
+        }
-        registers_lock
-            .soft_committed
-            .set_commit(opstamp, segment_entries);
-        registers_lock.delete_cursor.skip_to(opstamp);
     }
 
-    pub fn soft_commit(&self, opstamp: u64, segment_entries: Vec<SegmentEntry>) {
+    /// Marks a list of segments as in merge.
-        let mut registers_lock = self.write();
-        registers_lock.uncommitted.clear();
-        registers_lock
-            .soft_committed
-            .set_commit(opstamp, segment_entries);
-        registers_lock.delete_cursor.skip_to(opstamp);
-    }
-
-    /// Gets the list of segment_entries associated to a list of `segment_ids`.
-    /// This method is used when starting a merge operations.
     ///
     /// Returns an error if some segments are missing, or if
-    /// the `segment_ids` are not either all soft_committed or all
+    /// the `segment_ids` are not either all committed or all
     /// uncommitted.
     pub fn start_merge(&self, segment_ids: &[SegmentId]) -> TantivyResult<Vec<SegmentEntry>> {
         let registers_lock = self.read();
         let mut segment_entries = vec![];
-        if segment_ids.iter().all(|segment_id| registers_lock.uncommitted.contains_key(segment_id)) {
+        if registers_lock.uncommitted.contains_all(segment_ids) {
             for segment_id in segment_ids {
                 let segment_entry = registers_lock.uncommitted
                     .get(segment_id)
                     .expect("Segment id not found {}. Should never happen because of the contains all if-block.");
-                segment_entries.push(segment_entry.clone());
+                segment_entries.push(segment_entry);
             }
-        } else if registers_lock.soft_committed.contains_all(segment_ids) {
+        } else if registers_lock.committed.contains_all(segment_ids) {
             for segment_id in segment_ids {
-                let segment_entry = registers_lock.soft_committed
+                let segment_entry = registers_lock.committed
-                    .get(segment_id, &registers_lock.delete_cursor)
+                    .get(segment_id)
                     .expect("Segment id not found {}. Should never happen because of the contains all if-block.");
                 segment_entries.push(segment_entry);
             }
@@ -234,32 +160,35 @@ impl SegmentManager {
 
     pub fn add_segment(&self, segment_entry: SegmentEntry) {
         let mut registers_lock = self.write();
-        registers_lock
+        registers_lock.uncommitted.add_segment_entry(segment_entry);
-            .uncommitted
-            .insert(segment_entry.segment_id(), segment_entry);
     }
 
     pub fn end_merge(
         &self,
         before_merge_segment_ids: &[SegmentId],
-        after_merge_segment_entry: SegmentEntry
+        after_merge_segment_entry: SegmentEntry,
     ) {
         let mut registers_lock = self.write();
-
+        let target_register: &mut SegmentRegister = {
-        if before_merge_segment_ids.iter().all(|seg_id|
+            if registers_lock
-            registers_lock
                 .uncommitted
-                .contains_key(seg_id))
+                .contains_all(before_merge_segment_ids)
-        {
+            {
-            for segment_id in before_merge_segment_ids {
+                &mut registers_lock.uncommitted
-                registers_lock.uncommitted.remove(&segment_id);
+            } else if registers_lock
+                .committed
+                .contains_all(before_merge_segment_ids)
+            {
+                &mut registers_lock.committed
+            } else {
+                warn!("couldn't find segment in SegmentManager");
+                return;
             }
-            registers_lock.uncommitted.insert(after_merge_segment_entry.segment_id(),
+        };
-                                              after_merge_segment_entry);
+        for segment_id in before_merge_segment_ids {
-        } else {
+            target_register.remove_segment(segment_id);
-            registers_lock.committed.receive_merge(&before_merge_segment_ids, &after_merge_segment_entry);
-            registers_lock.soft_committed.receive_merge(&before_merge_segment_ids, &after_merge_segment_entry)
         }
+        target_register.add_segment_entry(after_merge_segment_entry);
     }
 
     pub fn committed_segment_metas(&self) -> Vec<SegmentMeta> {

src/indexer/segment_register.rs

@@ -16,8 +16,7 @@ use std::fmt::{self, Debug, Formatter};
 /// merge candidates.
 #[derive(Default)]
 pub struct SegmentRegister {
-    segment_states: HashMap<SegmentId, SegmentMeta>,
+    segment_states: HashMap<SegmentId, SegmentEntry>,
-    opstamp_constraint: u64,
 }
 
 impl Debug for SegmentRegister {
@@ -42,28 +41,23 @@ impl SegmentRegister {
     ) -> Vec<SegmentMeta> {
         self.segment_states
             .values()
-            .filter(|segment_meta| !in_merge_segment_ids.contains(&segment_meta.id()))
+            .filter(|segment_entry| !in_merge_segment_ids.contains(&segment_entry.segment_id()))
-            .cloned()
+            .map(|segment_entry| segment_entry.meta().clone())
             .collect()
     }
 
+    pub fn segment_entries(&self) -> Vec<SegmentEntry> {
+        self.segment_states.values().cloned().collect()
+    }
+
     pub fn segment_metas(&self) -> Vec<SegmentMeta> {
-        let mut segment_metas: Vec<SegmentMeta> = self
+        let mut segment_ids: Vec<SegmentMeta> = self
             .segment_states
             .values()
-            .cloned()
+            .map(|segment_entry| segment_entry.meta().clone())
             .collect();
-        segment_metas.sort_by_key(|meta| meta.id());
+        segment_ids.sort_by_key(SegmentMeta::id);
-        segment_metas
+        segment_ids
-    }
-
-    pub fn segment_entries(&self, delete_cursor: &DeleteCursor) -> Vec<SegmentEntry> {
-        self.segment_states
-            .values()
-            .map(|segment_meta| {
-                SegmentEntry::new(segment_meta.clone(), delete_cursor.clone(), None, self.opstamp_constraint)
-            })
-            .collect()
     }
 
     pub fn contains_all(&self, segment_ids: &[SegmentId]) -> bool {
@@ -72,77 +66,27 @@ impl SegmentRegister {
             .all(|segment_id| self.segment_states.contains_key(segment_id))
     }
 
-    pub fn receive_merge(&mut self,
+    pub fn add_segment_entry(&mut self, segment_entry: SegmentEntry) {
-                         before_merge_segment_ids: &[SegmentId],
-                         after_merge_segment_entry: &SegmentEntry) {
-        if after_merge_segment_entry.opstamp() != self.opstamp_constraint {
-            return;
-        }
-        if !self.contains_all(before_merge_segment_ids) {
-            return;
-        }
-        for segment_id in before_merge_segment_ids {
-            self.segment_states.remove(segment_id);
-        }
-        self.register_segment_entry(after_merge_segment_entry.clone());
-    }
-
-    /// Registers a `SegmentEntry`.
-    ///
-    /// If a segment entry associated to this `SegmentId` is already there,
-    /// override it with the new `SegmentEntry`.
-    pub fn register_segment_entry(&mut self, segment_entry: SegmentEntry) {
-        if self.opstamp_constraint != segment_entry.opstamp() {
-            panic!(format!(
-                "Invalid segment. Expect opstamp {}, got {}.",
-                self.opstamp_constraint,
-                segment_entry.opstamp()
-            ));
-        }
-        if segment_entry.meta().num_docs() == 0 {
-            return;
-        }
         let segment_id = segment_entry.segment_id();
-        // Check that we are ok with deletes.
+        self.segment_states.insert(segment_id, segment_entry);
-        self.segment_states.insert(segment_id, segment_entry.meta().clone());
-    }
-
-    pub fn set_commit(&mut self, opstamp: u64, segment_entries: Vec<SegmentEntry>) {
-        self.segment_states.clear();
-        self.opstamp_constraint = opstamp;
-        for segment_entry in segment_entries {
-            self.register_segment_entry(segment_entry);
-        }
     }
 
     pub fn remove_segment(&mut self, segment_id: &SegmentId) {
-        self.segment_states.remove(&segment_id);
+        self.segment_states.remove(segment_id);
     }
 
-    pub fn get(&self, segment_id: &SegmentId, delete_cursor: &DeleteCursor) -> Option<SegmentEntry> {
+    pub fn get(&self, segment_id: &SegmentId) -> Option<SegmentEntry> {
-        self.segment_states
+        self.segment_states.get(segment_id).cloned()
-            .get(&segment_id)
-            .map(|segment_meta|
-                SegmentEntry::new(
-                    segment_meta.clone(),
-                    delete_cursor.clone(),
-                    None,
-                    self.opstamp_constraint
-                ))
     }
 
-    pub fn new(
+    pub fn new(segment_metas: Vec<SegmentMeta>, delete_cursor: &DeleteCursor) -> SegmentRegister {
-        segment_metas: Vec<SegmentMeta>,
-        opstamp: u64,
-    ) -> SegmentRegister {
         let mut segment_states = HashMap::new();
         for segment_meta in segment_metas {
-            segment_states.insert(segment_meta.id(), segment_meta);
+            let segment_id = segment_meta.id();
-        }
+            let segment_entry = SegmentEntry::new(segment_meta, delete_cursor.clone(), None);
-        SegmentRegister {
+            segment_states.insert(segment_id, segment_entry);
-            segment_states,
-            opstamp_constraint: opstamp,
         }
+        SegmentRegister { segment_states }
     }
 }
 
@@ -171,22 +115,22 @@ mod tests {
         let segment_id_merged = SegmentId::generate_random();
 
         {
-            let segment_meta = SegmentMeta::new(segment_id_a, 1u32);
+            let segment_meta = SegmentMeta::new(segment_id_a, 0u32);
-            let segment_entry = SegmentEntry::new(segment_meta, delete_queue.cursor(), None, 0u64);
+            let segment_entry = SegmentEntry::new(segment_meta, delete_queue.cursor(), None);
-            segment_register.register_segment_entry(segment_entry);
+            segment_register.add_segment_entry(segment_entry);
         }
         assert_eq!(segment_ids(&segment_register), vec![segment_id_a]);
         {
-            let segment_meta = SegmentMeta::new(segment_id_b, 2u32);
+            let segment_meta = SegmentMeta::new(segment_id_b, 0u32);
-            let segment_entry = SegmentEntry::new(segment_meta, delete_queue.cursor(), None, 0u64);
+            let segment_entry = SegmentEntry::new(segment_meta, delete_queue.cursor(), None);
-            segment_register.register_segment_entry(segment_entry);
+            segment_register.add_segment_entry(segment_entry);
         }
+        segment_register.remove_segment(&segment_id_a);
+        segment_register.remove_segment(&segment_id_b);
         {
-            let segment_meta_merged = SegmentMeta::new(segment_id_merged, 3u32);
+            let segment_meta_merged = SegmentMeta::new(segment_id_merged, 0u32);
-            let segment_entry =
+            let segment_entry = SegmentEntry::new(segment_meta_merged, delete_queue.cursor(), None);
-                SegmentEntry::new(segment_meta_merged, delete_queue.cursor(), None, 0u64);
+            segment_register.add_segment_entry(segment_entry);
-            segment_register.receive_merge(&[segment_id_a, segment_id_b], &segment_entry);
-            segment_register.register_segment_entry(segment_entry);
         }
         assert_eq!(segment_ids(&segment_register), vec![segment_id_merged]);
     }

src/indexer/segment_updater.rs

@@ -125,7 +125,7 @@ fn perform_merge(
 
     let segment_meta = SegmentMeta::new(merged_segment.id(), num_docs);
 
-    let after_merge_segment_entry = SegmentEntry::new(segment_meta.clone(), delete_cursor, None, target_opstamp);
+    let after_merge_segment_entry = SegmentEntry::new(segment_meta.clone(), delete_cursor, None);
     Ok(after_merge_segment_entry)
 }
 
@@ -155,11 +155,8 @@ impl SegmentUpdater {
         stamper: Stamper,
         delete_cursor: &DeleteCursor,
     ) -> Result<SegmentUpdater> {
-
-        let index_meta = index.load_metas()?;
         let segments = index.searchable_segment_metas()?;
-        let opstamp = index_meta.opstamp;
+        let segment_manager = SegmentManager::from_segments(segments, delete_cursor);
-        let segment_manager = SegmentManager::from_segments(segments, delete_cursor, opstamp);
         let pool = CpuPoolBuilder::new()
             .name_prefix("segment_updater")
             .pool_size(1)
@@ -283,30 +280,14 @@ impl SegmentUpdater {
             .garbage_collect(|| self.0.segment_manager.list_files());
     }
 
-    pub fn commit(&self, opstamp: u64, payload: Option<String>, soft: bool) -> Result<()> {
+    pub fn commit(&self, opstamp: u64, payload: Option<String>) -> Result<()> {
         self.run_async(move |segment_updater| {
             if segment_updater.is_alive() {
                 let segment_entries = segment_updater
                     .purge_deletes(opstamp)
                     .expect("Failed purge deletes");
-                if soft {
+                segment_updater.0.segment_manager.commit(segment_entries);
-                    // Soft commit.
+                segment_updater.save_metas(opstamp, payload);
-                    //
-                    // The list `segment_entries` above is what we might want to use as searchable
-                    // segment. However, we do not want to mark them as committed, and we want
-                    // to keep the current set of committed segment.
-                    segment_updater.0.segment_manager.soft_commit(opstamp, segment_entries);
-                    // ... We do not save the meta file.
-                } else {
-                    // Hard_commit. We register the new segment entries as committed.
-                    segment_updater
-                        .0
-                        .segment_manager
-                        .commit(opstamp, segment_entries);
-                    // TODO error handling.
-                    segment_updater.save_metas(opstamp, payload);
-                    segment_updater.0.index.directory().flush().unwrap();
-                }
                 segment_updater.garbage_collect_files_exec();
                 segment_updater.consider_merge_options();
             }

src/indexer/segment_writer.rs

@@ -5,6 +5,7 @@ use fastfield::FastFieldsWriter;
 use fieldnorm::FieldNormsWriter;
 use indexer::segment_serializer::SegmentSerializer;
 use postings::MultiFieldPostingsWriter;
+use schema::FieldEntry;
 use schema::FieldType;
 use schema::Schema;
 use schema::Term;
@@ -53,7 +54,7 @@ impl SegmentWriter {
             schema
                 .fields()
                 .iter()
-                .map(|field_entry| field_entry.field_type())
+                .map(FieldEntry::field_type)
                 .map(|field_type| match *field_type {
                     FieldType::Str(ref text_options) => text_options
                         .get_indexing_options()

src/lib.rs

@@ -876,28 +876,28 @@ mod tests {
         let searcher = reader.searcher();
         let segment_reader: &SegmentReader = searcher.segment_reader(0);
         {
-            let fast_field_reader_res = segment_reader.fast_field_reader::<u64>(text_field);
+            let fast_field_reader_opt = segment_reader.fast_fields().u64(text_field);
-            assert!(fast_field_reader_res.is_err());
+            assert!(fast_field_reader_opt.is_none());
         }
         {
-            let fast_field_reader_res = segment_reader.fast_field_reader::<u64>(stored_int_field);
+            let fast_field_reader_opt = segment_reader.fast_fields().u64(stored_int_field);
-            assert!(fast_field_reader_res.is_err());
+            assert!(fast_field_reader_opt.is_none());
         }
         {
-            let fast_field_reader_res = segment_reader.fast_field_reader::<u64>(fast_field_signed);
+            let fast_field_reader_opt = segment_reader.fast_fields().u64(fast_field_signed);
-            assert!(fast_field_reader_res.is_err());
+            assert!(fast_field_reader_opt.is_none());
         }
         {
-            let fast_field_reader_res = segment_reader.fast_field_reader::<i64>(fast_field_signed);
+            let fast_field_reader_opt = segment_reader.fast_fields().i64(fast_field_signed);
-            assert!(fast_field_reader_res.is_ok());
+            assert!(fast_field_reader_opt.is_some());
-            let fast_field_reader = fast_field_reader_res.unwrap();
+            let fast_field_reader = fast_field_reader_opt.unwrap();
             assert_eq!(fast_field_reader.get(0), 4i64)
         }
 
         {
-            let fast_field_reader_res = segment_reader.fast_field_reader::<i64>(fast_field_signed);
+            let fast_field_reader_opt = segment_reader.fast_fields().i64(fast_field_signed);
-            assert!(fast_field_reader_res.is_ok());
+            assert!(fast_field_reader_opt.is_some());
-            let fast_field_reader = fast_field_reader_res.unwrap();
+            let fast_field_reader = fast_field_reader_opt.unwrap();
             assert_eq!(fast_field_reader.get(0), 4i64)
         }
     }

src/postings/block_search.rs

@@ -1,3 +1,5 @@
+use postings::compression::AlignedBuffer;
+
 /// This modules define the logic used to search for a doc in a given
 /// block. (at most 128 docs)
 ///
@@ -6,7 +8,7 @@
 
 #[cfg(target_arch = "x86_64")]
 mod sse2 {
-    use postings::compression::COMPRESSION_BLOCK_SIZE;
+    use postings::compression::{AlignedBuffer, COMPRESSION_BLOCK_SIZE};
     use std::arch::x86_64::__m128i as DataType;
     use std::arch::x86_64::_mm_add_epi32 as op_add;
     use std::arch::x86_64::_mm_cmplt_epi32 as op_lt;
@@ -23,9 +25,9 @@ mod sse2 {
     ///
     /// There is no early exit here. We simply count the
     /// number of elements that are `< target`.
-    pub fn linear_search_sse2_128(arr: &[u32], target: u32) -> usize {
+    pub(crate) fn linear_search_sse2_128(arr: &AlignedBuffer, target: u32) -> usize {
         unsafe {
-            let ptr = arr.as_ptr() as *const DataType;
+            let ptr = arr as *const AlignedBuffer as *const DataType;
             let vkey = set1(target as i32);
             let mut cnt = set0();
             // We work over 4 `__m128i` at a time.
@@ -47,14 +49,16 @@ mod sse2 {
     #[cfg(test)]
     mod test {
         use super::linear_search_sse2_128;
+        use postings::compression::{AlignedBuffer, COMPRESSION_BLOCK_SIZE};
 
         #[test]
         fn test_linear_search_sse2_128_u32() {
-            for i in 0..23 {
+            let mut block = [0u32; COMPRESSION_BLOCK_SIZE];
-                dbg!(i);
+            for el in 0u32..128u32 {
-                let arr: Vec<u32> = (0..128).map(|el| el * 2 + 1 << 18).collect();
+                block[el as usize] = el * 2 + 1 << 18;
-                assert_eq!(linear_search_sse2_128(&arr, arr[64] + 1), 65);
             }
+            let target = block[64] + 1;
+            assert_eq!(linear_search_sse2_128(&AlignedBuffer(block), target), 65);
         }
     }
 }
@@ -127,17 +131,21 @@ impl BlockSearcher {
     /// then we use a different implementation that does an exhaustive linear search over
     /// the full block whenever the block is full (`len == 128`). It is surprisingly faster, most likely because of the lack
     /// of branch.
-    pub fn search_in_block(&self, block_docs: &[u32], start: usize, target: u32) -> usize {
+    pub(crate) fn search_in_block(
+        self,
+        block_docs: &AlignedBuffer,
+        len: usize,
+        start: usize,
+        target: u32,
+    ) -> usize {
         #[cfg(target_arch = "x86_64")]
         {
             use postings::compression::COMPRESSION_BLOCK_SIZE;
-            if *self == BlockSearcher::SSE2 {
+            if self == BlockSearcher::SSE2 && len == COMPRESSION_BLOCK_SIZE {
-                if block_docs.len() == COMPRESSION_BLOCK_SIZE {
+                return sse2::linear_search_sse2_128(block_docs, target);
-                    return sse2::linear_search_sse2_128(block_docs, target);
-                }
             }
         }
-        start + galloping(&block_docs[start..], target)
+        start + galloping(&block_docs.0[start..len], target)
     }
 }
 
@@ -158,6 +166,7 @@ mod tests {
     use super::exponential_search;
     use super::linear_search;
     use super::BlockSearcher;
+    use postings::compression::{AlignedBuffer, COMPRESSION_BLOCK_SIZE};
 
     #[test]
     fn test_linear_search() {
@@ -186,8 +195,19 @@ mod tests {
 
     fn util_test_search_in_block(block_searcher: BlockSearcher, block: &[u32], target: u32) {
         let cursor = search_in_block_trivial_but_slow(block, target);
+        assert!(block.len() < COMPRESSION_BLOCK_SIZE);
+        let mut output_buffer = [u32::max_value(); COMPRESSION_BLOCK_SIZE];
+        output_buffer[..block.len()].copy_from_slice(block);
         for i in 0..cursor {
-            assert_eq!(block_searcher.search_in_block(block, i, target), cursor);
+            assert_eq!(
+                block_searcher.search_in_block(
+                    &AlignedBuffer(output_buffer),
+                    block.len(),
+                    i,
+                    target
+                ),
+                cursor
+            );
         }
     }
 

src/postings/compression/mod.rs

@@ -46,11 +46,11 @@ impl BlockEncoder {
 /// We ensure that the OutputBuffer is align on 128 bits
 /// in order to run SSE2 linear search on it.
 #[repr(align(128))]
-struct OutputBuffer([u32; COMPRESSION_BLOCK_SIZE + 1]);
+pub(crate) struct AlignedBuffer(pub [u32; COMPRESSION_BLOCK_SIZE]);
 
 pub struct BlockDecoder {
     bitpacker: BitPacker4x,
-    output: OutputBuffer,
+    output: AlignedBuffer,
     pub output_len: usize,
 }
 
@@ -60,11 +60,9 @@ impl BlockDecoder {
     }
 
     pub fn with_val(val: u32) -> BlockDecoder {
-        let mut output = [val; COMPRESSION_BLOCK_SIZE + 1];
-        output[COMPRESSION_BLOCK_SIZE] = 0u32;
         BlockDecoder {
             bitpacker: BitPacker4x::new(),
-            output: OutputBuffer(output),
+            output: AlignedBuffer([val; COMPRESSION_BLOCK_SIZE]),
             output_len: 0,
         }
     }
@@ -91,6 +89,11 @@ impl BlockDecoder {
         &self.output.0[..self.output_len]
     }
 
+    #[inline]
+    pub(crate) fn output_aligned(&self) -> (&AlignedBuffer, usize) {
+        (&self.output, self.output_len)
+    }
+
     #[inline]
     pub fn output(&self, idx: usize) -> u32 {
         self.output.0[idx]

src/postings/mod.rs

@@ -55,13 +55,15 @@ pub mod tests {
     use fieldnorm::FieldNormReader;
     use indexer::operation::AddOperation;
     use indexer::SegmentWriter;
+    use merge_policy::NoMergePolicy;
     use query::Scorer;
     use rand::rngs::StdRng;
     use rand::{Rng, SeedableRng};
-    use schema::Field;
-    use schema::IndexRecordOption;
     use schema::{Document, Schema, Term, INDEXED, STRING, TEXT};
+    use schema::{Field, TextOptions};
+    use schema::{IndexRecordOption, TextFieldIndexing};
     use std::iter;
+    use tokenizer::{SimpleTokenizer, MAX_TOKEN_LEN};
     use DocId;
     use Score;
 
@@ -160,6 +162,52 @@ pub mod tests {
         }
     }
 
+    #[test]
+    pub fn test_drop_token_that_are_too_long() {
+        let ok_token_text: String = iter::repeat('A').take(MAX_TOKEN_LEN).collect();
+        let mut exceeding_token_text: String = iter::repeat('A').take(MAX_TOKEN_LEN + 1).collect();
+        exceeding_token_text.push_str(" hello");
+        let mut schema_builder = Schema::builder();
+        let text_options = TextOptions::default().set_indexing_options(
+            TextFieldIndexing::default()
+                .set_index_option(IndexRecordOption::WithFreqsAndPositions)
+                .set_tokenizer("simple_no_truncation"),
+        );
+        let text_field = schema_builder.add_text_field("text", text_options);
+        let schema = schema_builder.build();
+        let index = Index::create_in_ram(schema.clone());
+        index
+            .tokenizers()
+            .register("simple_no_truncation", SimpleTokenizer);
+        let reader = index.reader().unwrap();
+        let mut index_writer = index.writer_with_num_threads(1, 3_000_000).unwrap();
+        index_writer.set_merge_policy(Box::new(NoMergePolicy));
+        {
+            index_writer.add_document(doc!(text_field=>exceeding_token_text));
+            index_writer.commit().unwrap();
+            reader.reload().unwrap();
+            let searcher = reader.searcher();
+            let segment_reader = searcher.segment_reader(0u32);
+            let inverted_index = segment_reader.inverted_index(text_field);
+            assert_eq!(inverted_index.terms().num_terms(), 1);
+            let mut bytes = vec![];
+            assert!(inverted_index.terms().ord_to_term(0, &mut bytes));
+            assert_eq!(&bytes, b"hello");
+        }
+        {
+            index_writer.add_document(doc!(text_field=>ok_token_text.clone()));
+            index_writer.commit().unwrap();
+            reader.reload().unwrap();
+            let searcher = reader.searcher();
+            let segment_reader = searcher.segment_reader(1u32);
+            let inverted_index = segment_reader.inverted_index(text_field);
+            assert_eq!(inverted_index.terms().num_terms(), 1);
+            let mut bytes = vec![];
+            assert!(inverted_index.terms().ord_to_term(0, &mut bytes));
+            assert_eq!(&bytes[..], ok_token_text.as_bytes());
+        }
+    }
+
     #[test]
     pub fn test_position_and_fieldnorm1() {
         let mut positions = Vec::new();

src/postings/postings_writer.rs

@@ -12,8 +12,8 @@ use std::io;
 use std::marker::PhantomData;
 use std::ops::DerefMut;
 use termdict::TermOrdinal;
-use tokenizer::Token;
 use tokenizer::TokenStream;
+use tokenizer::{Token, MAX_TOKEN_LEN};
 use DocId;
 use Result;
 
@@ -210,8 +210,18 @@ pub trait PostingsWriter {
     ) -> u32 {
         let mut term = Term::for_field(field);
         let mut sink = |token: &Token| {
-            term.set_text(token.text.as_str());
+            // We skip all tokens with a len greater than u16.
-            self.subscribe(term_index, doc_id, token.position as u32, &term, heap);
+            if token.text.len() <= MAX_TOKEN_LEN {
+                term.set_text(token.text.as_str());
+                self.subscribe(term_index, doc_id, token.position as u32, &term, heap);
+            } else {
+                info!(
+                    "A token exceeding MAX_TOKEN_LEN ({}>{}) was dropped. Search for \
+                     MAX_TOKEN_LEN in the documentation for more information.",
+                    token.text.len(),
+                    MAX_TOKEN_LEN
+                );
+            }
         };
         token_stream.process(&mut sink)
     }

src/postings/segment_postings.rs

@@ -4,7 +4,7 @@ use common::{BinarySerializable, VInt};
 use docset::{DocSet, SkipResult};
 use owned_read::OwnedRead;
 use positions::PositionReader;
-use postings::compression::compressed_block_size;
+use postings::compression::{compressed_block_size, AlignedBuffer};
 use postings::compression::{BlockDecoder, VIntDecoder, COMPRESSION_BLOCK_SIZE};
 use postings::serializer::PostingsSerializer;
 use postings::BlockSearcher;
@@ -130,9 +130,11 @@ impl DocSet for SegmentPostings {
     // next needs to be called a first time to point to the correct element.
     #[inline]
     fn advance(&mut self) -> bool {
-        if self.position_computer.is_some() {
+        if self.position_computer.is_some() && self.cur < COMPRESSION_BLOCK_SIZE {
             let term_freq = self.term_freq() as usize;
-            self.position_computer.as_mut().unwrap().add_skip(term_freq);
+            if let Some(position_computer) = self.position_computer.as_mut() {
+                position_computer.add_skip(term_freq);
+            }
         }
         self.cur += 1;
         if self.cur >= self.block_cursor.block_len() {
@@ -167,7 +169,6 @@ impl DocSet for SegmentPostings {
 
         // skip blocks until one that might contain the target
         // check if we need to go to the next block
-        let need_positions = self.position_computer.is_some();
         let mut sum_freqs_skipped: u32 = 0;
         if !self
             .block_cursor
@@ -181,7 +182,7 @@ impl DocSet for SegmentPostings {
             // we are not in the right block.
             //
             // First compute all of the freqs skipped from the current block.
-            if need_positions {
+            if self.position_computer.is_some() {
                 sum_freqs_skipped = self.block_cursor.freqs()[self.cur..].iter().sum();
                 match self.block_cursor.skip_to(target) {
                     BlockSegmentPostingsSkipResult::Success(block_skip_freqs) => {
@@ -200,24 +201,21 @@ impl DocSet for SegmentPostings {
             self.cur = 0;
         }
 
+        let cur = self.cur;
+
         // we're in the right block now, start with an exponential search
-        let block_docs = self.block_cursor.docs();
+        let (output, len) = self.block_cursor.docs_aligned();
         let new_cur = self
             .block_searcher
-            .search_in_block(&block_docs, self.cur, target);
+            .search_in_block(&output, len, cur, target);
-        if need_positions {
+        if let Some(position_computer) = self.position_computer.as_mut() {
-            sum_freqs_skipped += self.block_cursor.freqs()[self.cur..new_cur]
+            sum_freqs_skipped += self.block_cursor.freqs()[cur..new_cur].iter().sum::<u32>();
-                .iter()
+            position_computer.add_skip(sum_freqs_skipped as usize);
-                .sum::<u32>();
-            self.position_computer
-                .as_mut()
-                .unwrap()
-                .add_skip(sum_freqs_skipped as usize);
         }
         self.cur = new_cur;
 
         // `doc` is now the first element >= `target`
-        let doc = block_docs[new_cur];
+        let doc = output.0[new_cur];
         debug_assert!(doc >= target);
         if doc == target {
             SkipResult::Reached
@@ -227,12 +225,16 @@ impl DocSet for SegmentPostings {
     }
 
     /// Return the current document's `DocId`.
+    ///
+    /// # Panics
+    ///
+    /// Will panics if called without having called advance before.
     #[inline]
     fn doc(&self) -> DocId {
         let docs = self.block_cursor.docs();
         debug_assert!(
             self.cur < docs.len(),
-            "Have you forgotten to call `.advance()` at least once before calling .doc()."
+            "Have you forgotten to call `.advance()` at least once before calling `.doc()`                                      ."
         );
         docs[self.cur]
     }
@@ -264,17 +266,33 @@ impl HasLen for SegmentPostings {
 }
 
 impl Postings for SegmentPostings {
+    /// Returns the frequency associated to the current document.
+    /// If the schema is set up so that no frequency have been encoded,
+    /// this method should always return 1.
+    ///
+    /// # Panics
+    ///
+    /// Will panics if called without having called advance before.
     fn term_freq(&self) -> u32 {
+        debug_assert!(
+            // Here we do not use the len of `freqs()`
+            // because it is actually ok to request for the freq of doc
+            // even if no frequency were encoded for the field.
+            //
+            // In that case we hit the block just as if the frequency had been
+            // decoded. The block is simply prefilled by the value 1.
+            self.cur < COMPRESSION_BLOCK_SIZE,
+            "Have you forgotten to call `.advance()` at least once before calling \
+             `.term_freq()`."
+        );
         self.block_cursor.freq(self.cur)
     }
 
     fn positions_with_offset(&mut self, offset: u32, output: &mut Vec<u32>) {
-        if self.position_computer.is_some() {
+        let term_freq = self.term_freq() as usize;
-            output.resize(self.term_freq() as usize, 0u32);
+        if let Some(position_comp) = self.position_computer.as_mut() {
-            self.position_computer
+            output.resize(term_freq, 0u32);
-                .as_mut()
+            position_comp.positions_with_offset(offset, &mut output[..]);
-                .unwrap()
-                .positions_with_offset(offset, &mut output[..])
         } else {
             output.clear();
         }
@@ -396,6 +414,10 @@ impl BlockSegmentPostings {
         self.doc_decoder.output_array()
     }
 
+    pub(crate) fn docs_aligned(&self) -> (&AlignedBuffer, usize) {
+        self.doc_decoder.output_aligned()
+    }
+
     /// Return the document at index `idx` of the block.
     #[inline]
     pub fn doc(&self, idx: usize) -> u32 {
@@ -592,6 +614,7 @@ mod tests {
     use common::HasLen;
     use core::Index;
     use docset::DocSet;
+    use postings::postings::Postings;
     use schema::IndexRecordOption;
     use schema::Schema;
     use schema::Term;
@@ -608,6 +631,18 @@ mod tests {
         assert_eq!(postings.len(), 0);
     }
 
+    #[test]
+    #[should_panic(expected = "Have you forgotten to call `.advance()`")]
+    fn test_panic_if_doc_called_before_advance() {
+        SegmentPostings::empty().doc();
+    }
+
+    #[test]
+    #[should_panic(expected = "Have you forgotten to call `.advance()`")]
+    fn test_panic_if_freq_called_before_advance() {
+        SegmentPostings::empty().term_freq();
+    }
+
     #[test]
     fn test_empty_block_segment_postings() {
         let mut postings = BlockSegmentPostings::empty();

src/postings/serializer.rs

@@ -14,7 +14,7 @@ use termdict::{TermDictionaryBuilder, TermOrdinal};
 use DocId;
 use Result;
 
-/// `PostingsSerializer` is in charge of serializing
+/// `InvertedIndexSerializer` is in charge of serializing
 /// postings on disk, in the
 /// * `.idx` (inverted index)
 /// * `.pos` (positions file)
@@ -54,7 +54,7 @@ pub struct InvertedIndexSerializer {
 }
 
 impl InvertedIndexSerializer {
-    /// Open a new `PostingsSerializer` for the given segment
+    /// Open a new `InvertedIndexSerializer` for the given segment
     fn create(
         terms_write: CompositeWrite<WritePtr>,
         postings_write: CompositeWrite<WritePtr>,
@@ -175,7 +175,7 @@ impl<'a> FieldSerializer<'a> {
         let positions_idx = self
             .positions_serializer_opt
             .as_ref()
-            .map(|positions_serializer| positions_serializer.positions_idx())
+            .map(PositionSerializer::positions_idx)
             .unwrap_or(0u64);
         TermInfo {
             doc_freq: 0,

src/query/intersection.rs

@@ -214,6 +214,102 @@ impl<TDocSet: DocSet, TOtherDocSet: DocSet> DocSet for Intersection<TDocSet, TOt
     }
 }
 
+// `ahead` is assumed to be initialized (ahead.advance() has been called at least once,
+// and this returned true).
+//
+// If behind is either uninitialized or `ahead.doc() > behind.doc()`.
+fn next_in_intersection<'a, TScorer: Scorer>(
+    ahead: &'a mut TScorer,
+    behind: &'a mut TScorer,
+) -> Option<DocId> {
+    let candidate = ahead.doc();
+    match behind.skip_next(candidate) {
+        SkipResult::Reached => Some(candidate),
+        SkipResult::OverStep => {
+            // yeah for tail-recursion
+            next_in_intersection(behind, ahead)
+        }
+        SkipResult::End => None,
+    }
+}
+
+enum SkipResultComplex {
+    Reached,
+    Overstep { other_ord: usize, candidate: DocId },
+    End,
+}
+
+fn skip_several_scorers<TDocSet: DocSet>(
+    others: &mut [TDocSet],
+    except_candidate_ord: usize,
+    target: DocId,
+) -> SkipResultComplex {
+    for (ord, docset) in others.iter_mut().enumerate() {
+        // `candidate_ord` is already at the
+        // right position.
+        //
+        // Calling `skip_next` would advance this docset
+        // and miss it.
+        if ord == except_candidate_ord {
+            continue;
+        }
+        match docset.skip_next(target) {
+            SkipResult::Reached => {}
+            SkipResult::OverStep => {
+                return SkipResultComplex::Overstep {
+                    other_ord: ord,
+                    candidate: docset.doc(),
+                };
+            }
+            SkipResult::End => {
+                return SkipResultComplex::End;
+            }
+        }
+    }
+    SkipResultComplex::Reached
+}
+
+fn for_each<'a, TScorer: Scorer, TOtherscorer: Scorer>(
+    left: &'a mut TScorer,
+    right: &'a mut TScorer,
+    others: &'a mut [TOtherscorer],
+    callback: &mut FnMut(DocId, Score),
+) {
+    let mut other_candidate_ord: usize = usize::max_value();
+    if !left.advance() {
+        return;
+    }
+    while let Some(candidate) = next_in_intersection(left, right) {
+        // test the remaining scorers
+        match skip_several_scorers(others, other_candidate_ord, candidate) {
+            SkipResultComplex::Reached => {
+                let intersection_score: Score = left.score()
+                    + right.score()
+                    + others.iter_mut().map(|other| other.score()).sum::<Score>();
+                callback(candidate, intersection_score);
+                if !left.advance() {
+                    return;
+                }
+            }
+            SkipResultComplex::Overstep {
+                other_ord,
+                candidate,
+            } => match left.skip_next(candidate) {
+                SkipResult::End => {
+                    return;
+                }
+                SkipResult::Reached => {
+                    other_candidate_ord = other_ord;
+                }
+                SkipResult::OverStep => other_candidate_ord = usize::max_value(),
+            },
+            SkipResultComplex::End => {
+                return;
+            }
+        }
+    }
+}
+
 impl<TScorer, TOtherScorer> Scorer for Intersection<TScorer, TOtherScorer>
 where
     TScorer: Scorer,
@@ -224,6 +320,10 @@ where
             + self.right.score()
             + self.others.iter_mut().map(Scorer::score).sum::<Score>()
     }
+
+    fn for_each(&mut self, callback: &mut FnMut(DocId, Score)) {
+        for_each(&mut self.left, &mut self.right, &mut self.others, callback);
+    }
 }
 
 #[cfg(test)]

src/query/phrase_query/phrase_query.rs

@@ -4,6 +4,7 @@ use error::TantivyError;
 use query::bm25::BM25Weight;
 use query::Query;
 use query::Weight;
+use schema::IndexRecordOption;
 use schema::{Field, Term};
 use std::collections::BTreeSet;
 use Result;
@@ -83,7 +84,7 @@ impl Query for PhraseQuery {
         let has_positions = field_entry
             .field_type()
             .get_index_record_option()
-            .map(|index_record_option| index_record_option.has_positions())
+            .map(IndexRecordOption::has_positions)
             .unwrap_or(false);
         if !has_positions {
             let field_name = field_entry.name();

src/query/query_parser/query_grammar.rs

@@ -1,6 +1,7 @@
 #![cfg_attr(feature = "cargo-clippy", allow(clippy::unneeded_field_pattern))]
 #![cfg_attr(feature = "cargo-clippy", allow(clippy::toplevel_ref_arg))]
 
+use super::query_grammar;
 use super::user_input_ast::*;
 use combine::char::*;
 use combine::error::StreamError;
@@ -22,7 +23,7 @@ parser! {
 parser! {
     fn word[I]()(I) -> String
     where [I: Stream<Item = char>] {
-        many1(satisfy(|c: char| c.is_alphanumeric()))
+        many1(satisfy(char::is_alphanumeric))
                .and_then(|s: String| {
                    match s.as_str() {
                      "OR" => Err(StreamErrorFor::<I>::unexpected_static_message("OR")),
@@ -62,7 +63,7 @@ parser! {
     fn negative_number[I]()(I) -> String
     where [I: Stream<Item = char>]
     {
-            (char('-'), many1(satisfy(|c: char| c.is_numeric())))
+            (char('-'), many1(satisfy(char::is_numeric)))
                 .map(|(s1, s2): (char, String)| format!("{}{}", s1, s2))
     }
 }
@@ -184,7 +185,7 @@ parser! {
                         }
                     )
                 )
-                .map(|el| el.into_dnf())
+                .map(query_grammar::Element::into_dnf)
                 .map(|fnd| {
                     if fnd.len() == 1 {
                         UserInputAST::and(fnd.into_iter().next().unwrap()) //< safe

src/query/scorer.rs

@@ -16,6 +16,9 @@ pub trait Scorer: downcast_rs::Downcast + DocSet + 'static {
 
     /// Iterates through all of the document matched by the DocSet
     /// `DocSet` and push the scored documents to the collector.
+    ///
+    /// This method assumes that the Scorer is brand new, and `.advance()`
+    /// and `.skip()` haven't been called yet.
     fn for_each(&mut self, callback: &mut FnMut(DocId, Score)) {
         while self.advance() {
             callback(self.doc(), self.score());

src/query/term_query/mod.rs

@@ -98,4 +98,20 @@ mod tests {
         }
     }
 
+    #[test]
+    fn test_term_query_count_when_there_are_deletes() {
+        let mut schema_builder = Schema::builder();
+        let text_field = schema_builder.add_text_field("text", TEXT);
+        let schema = schema_builder.build();
+        let index = Index::create_in_ram(schema);
+        let mut index_writer = index.writer_with_num_threads(1, 5_000_000).unwrap();
+        index_writer.add_document(doc!(text_field=>"a b"));
+        index_writer.add_document(doc!(text_field=>"a c"));
+        index_writer.delete_term(Term::from_field_text(text_field, "b"));
+        index_writer.commit().unwrap();
+        let term_a = Term::from_field_text(text_field, "a");
+        let term_query = TermQuery::new(term_a, IndexRecordOption::Basic);
+        let reader = index.reader().unwrap();
+        assert_eq!(term_query.count(&*reader.searcher()).unwrap(), 1);
+    }
 }

src/query/term_query/term_weight.rs

@@ -39,15 +39,15 @@ impl Weight for TermWeight {
     }
 
     fn count(&self, reader: &SegmentReader) -> Result<u32> {
-        if reader.num_deleted_docs() == 0 {
+        if let Some(delete_bitset) = reader.delete_bitset() {
+            Ok(self.scorer(reader)?.count(delete_bitset))
+        } else {
             let field = self.term.field();
             Ok(reader
                 .inverted_index(field)
                 .get_term_info(&self.term)
                 .map(|term_info| term_info.doc_freq)
                 .unwrap_or(0))
-        } else {
-            Ok(self.scorer(reader)?.count())
         }
     }
 }

src/query/union.rs

@@ -96,7 +96,7 @@ fn refill<TScorer: Scorer, TScoreCombiner: ScoreCombiner>(
 
 impl<TScorer: Scorer, TScoreCombiner: ScoreCombiner> Union<TScorer, TScoreCombiner> {
     fn refill(&mut self) -> bool {
-        if let Some(min_doc) = self.docsets.iter_mut().map(|docset| docset.doc()).min() {
+        if let Some(min_doc) = self.docsets.iter().map(DocSet::doc).min() {
             self.offset = min_doc;
             self.cursor = 0;
             refill(
@@ -145,7 +145,7 @@ where
         }
     }
 
-    fn count(&mut self) -> u32 {
+    fn count_including_deleted(&mut self) -> u32 {
         let mut count = self.bitsets[self.cursor..HORIZON_NUM_TINYBITSETS]
             .iter()
             .map(|bitset| bitset.len())
@@ -163,6 +163,8 @@ where
         count
     }
 
+    // TODO implement `count` efficiently.
+
     fn skip_next(&mut self, target: DocId) -> SkipResult {
         if !self.advance() {
             return SkipResult::End;
@@ -258,6 +260,23 @@ where
     fn score(&mut self) -> Score {
         self.score
     }
+
+    fn for_each(&mut self, callback: &mut FnMut(DocId, Score)) {
+        // TODO how do we deal with the fact that people may have called .advance() before.
+        while self.refill() {
+            let offset = self.offset;
+            for cursor in 0..HORIZON_NUM_TINYBITSETS {
+                while let Some(val) = self.bitsets[cursor].pop_lowest() {
+                    let delta = val + (cursor as u32) * 64;
+                    let doc = offset + delta;
+                    let score_combiner = &mut self.scores[delta as usize];
+                    let score = score_combiner.score();
+                    callback(doc, score);
+                    score_combiner.clear();
+                }
+            }
+        }
+    }
 }
 
 #[cfg(test)]
@@ -300,7 +319,7 @@ mod tests {
             count += 1;
         }
         assert!(!union_expected.advance());
-        assert_eq!(count, make_union().count());
+        assert_eq!(count, make_union().count_including_deleted());
     }
 
     #[test]

src/query/weight.rs

@@ -13,6 +13,11 @@ pub trait Weight: Send + Sync + 'static {
 
     /// Returns the number documents within the given `SegmentReader`.
     fn count(&self, reader: &SegmentReader) -> Result<u32> {
-        Ok(self.scorer(reader)?.count())
+        let mut scorer = self.scorer(reader)?;
+        if let Some(delete_bitset) = reader.delete_bitset() {
+            Ok(scorer.count(delete_bitset))
+        } else {
+            Ok(scorer.count_including_deleted())
+        }
     }
 }

src/reader/mod.rs

@@ -10,7 +10,6 @@ use Index;
 use Result;
 use Searcher;
 use SegmentReader;
-use schema::Schema;
 
 /// Defines when a new version of the index should be reloaded.
 ///
@@ -159,11 +158,6 @@ pub struct IndexReader {
 }
 
 impl IndexReader {
-
-    pub fn schema(&self) -> Schema {
-        self.inner.index.schema()
-    }
-
     /// Update searchers so that they reflect the state of the last
     /// `.commit()`.
     ///

src/schema/document.rs

@@ -128,7 +128,7 @@ impl Document {
         self.field_values
             .iter()
             .filter(|field_value| field_value.field() == field)
-            .map(|field_value| field_value.value())
+            .map(FieldValue::value)
             .collect()
     }
 
@@ -137,7 +137,7 @@ impl Document {
         self.field_values
             .iter()
             .find(|field_value| field_value.field() == field)
-            .map(|field_value| field_value.value())
+            .map(FieldValue::value)
     }
 }
 

src/schema/field_type.rs

@@ -4,6 +4,7 @@ use schema::{IntOptions, TextOptions};
 
 use schema::Facet;
 use schema::IndexRecordOption;
+use schema::TextFieldIndexing;
 use schema::Value;
 use serde_json::Value as JsonValue;
 
@@ -94,7 +95,7 @@ impl FieldType {
         match *self {
             FieldType::Str(ref text_options) => text_options
                 .get_indexing_options()
-                .map(|indexing_options| indexing_options.index_option()),
+                .map(TextFieldIndexing::index_option),
             FieldType::U64(ref int_options)
             | FieldType::I64(ref int_options)
             | FieldType::Date(ref int_options) => {

src/schema/schema.rs

@@ -130,7 +130,16 @@ impl SchemaBuilder {
         self.add_field(field_entry)
     }
 
-    /// Adds a fast bytes field to the schema
+    /// Adds a fast bytes field to the schema.
+    ///
+    /// Bytes field are not searchable and are only used
+    /// as fast field, to associate any kind of payload
+    /// to a document.
+    ///
+    /// For instance, learning-to-rank often requires to access
+    /// some document features at scoring time.
+    /// These can be serializing and stored as a bytes field to
+    /// get access rapidly when scoring each document.
     pub fn add_bytes_field(&mut self, field_name: &str) -> Field {
         let field_entry = FieldEntry::new_bytes(field_name.to_string());
         self.add_field(field_entry)
@@ -224,7 +233,7 @@ impl Schema {
             let field_name = self.get_field_name(field);
             let values: Vec<Value> = field_values
                 .into_iter()
-                .map(|field_val| field_val.value())
+                .map(FieldValue::value)
                 .cloned()
                 .collect();
             field_map.insert(field_name.to_string(), values);

src/snippet/mod.rs

@@ -1,6 +1,7 @@
 use htmlescape::encode_minimal;
 use query::Query;
 use schema::Field;
+use schema::Value;
 use std::cmp::Ordering;
 use std::collections::BTreeMap;
 use std::collections::BTreeSet;
@@ -303,7 +304,7 @@ impl SnippetGenerator {
         let text: String = doc
             .get_all(self.field)
             .into_iter()
-            .flat_map(|val| val.text())
+            .flat_map(Value::text)
             .collect::<Vec<&str>>()
             .join(" ");
         self.snippet(&text)

src/space_usage/mod.rs

@@ -227,7 +227,7 @@ pub struct PerFieldSpaceUsage {
 
 impl PerFieldSpaceUsage {
     pub(crate) fn new(fields: HashMap<Field, FieldUsage>) -> PerFieldSpaceUsage {
-        let total = fields.values().map(|x| x.total()).sum();
+        let total = fields.values().map(FieldUsage::total).sum();
         PerFieldSpaceUsage { fields, total }
     }
 

src/tokenizer/lower_caser.rs

@@ -44,18 +44,17 @@ where
     }
 
     fn advance(&mut self) -> bool {
-        if self.tail.advance() {
+        if !self.tail.advance() {
-            if self.token_mut().text.is_ascii() {
+            return false;
-                // fast track for ascii.
-                self.token_mut().text.make_ascii_lowercase();
-            } else {
-                to_lowercase_unicode(&mut self.tail.token_mut().text, &mut self.buffer);
-                mem::swap(&mut self.tail.token_mut().text, &mut self.buffer);
-            }
-            true
-        } else {
-            false
         }
+        if self.token_mut().text.is_ascii() {
+            // fast track for ascii.
+            self.token_mut().text.make_ascii_lowercase();
+        } else {
+            to_lowercase_unicode(&mut self.tail.token_mut().text, &mut self.buffer);
+            mem::swap(&mut self.tail.token_mut().text, &mut self.buffer);
+        }
+        true
     }
 }
 

src/tokenizer/mod.rs

@@ -97,6 +97,8 @@
 //! If you built your schema programmatically, a complete example
 //! could like this for instance.
 //!
+//! Note that tokens with a len greater or equal to [`MAX_TOKEN_LEN`](./constant.MAX_TOKEN_LEN.html).
+//!
 //! # Example
 //!
 //! ```
@@ -129,6 +131,7 @@
 //! ```
 //!
 mod alphanum_only;
+mod ascii_folding_filter;
 mod facet_tokenizer;
 mod lower_caser;
 mod ngram_tokenizer;
@@ -142,6 +145,7 @@ mod tokenizer;
 mod tokenizer_manager;
 
 pub use self::alphanum_only::AlphaNumOnlyFilter;
+pub use self::ascii_folding_filter::AsciiFoldingFilter;
 pub use self::facet_tokenizer::FacetTokenizer;
 pub use self::lower_caser::LowerCaser;
 pub use self::ngram_tokenizer::NgramTokenizer;
@@ -157,6 +161,13 @@ pub use self::tokenizer::BoxedTokenizer;
 pub use self::tokenizer::{Token, TokenFilter, TokenStream, Tokenizer};
 pub use self::tokenizer_manager::TokenizerManager;
 
+/// Maximum authorized len (in bytes) for a token.
+///
+/// Tokenizer are in charge of not emitting tokens larger than this value.
+/// Currently, if a faulty tokenizer implementation emits tokens with a length larger than
+/// `2^16 - 1 - 4`, the token will simply be ignored downstream.
+pub const MAX_TOKEN_LEN: usize = u16::max_value() as usize - 4;
+
 #[cfg(test)]
 pub mod tests {
     use super::{
@@ -228,27 +239,27 @@ pub mod tests {
     fn test_non_en_tokenizer() {
         let tokenizer_manager = TokenizerManager::default();
         tokenizer_manager.register(
-            "es_stem",
+            "el_stem",
             SimpleTokenizer
                 .filter(RemoveLongFilter::limit(40))
                 .filter(LowerCaser)
-                .filter(Stemmer::new(Language::Spanish)),
+                .filter(Stemmer::new(Language::Greek)),
         );
-        let en_tokenizer = tokenizer_manager.get("es_stem").unwrap();
+        let en_tokenizer = tokenizer_manager.get("el_stem").unwrap();
         let mut tokens: Vec<Token> = vec![];
         {
             let mut add_token = |token: &Token| {
                 tokens.push(token.clone());
             };
             en_tokenizer
-                .token_stream("Hola, feliz contribuyente!")
+                .token_stream("Καλημέρα, χαρούμενε φορολογούμενε!")
                 .process(&mut add_token);
         }
 
         assert_eq!(tokens.len(), 3);
-        assert_token(&tokens[0], 0, "hola", 0, 4);
+        assert_token(&tokens[0], 0, "καλημερ", 0, 16);
-        assert_token(&tokens[1], 1, "feliz", 6, 11);
+        assert_token(&tokens[1], 1, "χαρουμεν", 18, 36);
-        assert_token(&tokens[2], 2, "contribuyent", 12, 25);
+        assert_token(&tokens[2], 2, "φορολογουμεν", 37, 63);
     }
 
     #[test]

src/tokenizer/raw_tokenizer.rs

@@ -29,12 +29,9 @@ impl<'a> Tokenizer<'a> for RawTokenizer {
 
 impl TokenStream for RawTokenStream {
     fn advance(&mut self) -> bool {
-        if self.has_token {
+        let result = self.has_token;
-            self.has_token = false;
+        self.has_token = false;
-            true
+        result
-        } else {
-            false
-        }
     }
 
     fn token(&self) -> &Token {

src/tokenizer/remove_long.rs

@@ -91,7 +91,6 @@ where
                 return true;
             }
         }
-
         false
     }
 }

src/tokenizer/simple_tokenizer.rs

@@ -38,23 +38,16 @@ impl<'a> TokenStream for SimpleTokenStream<'a> {
     fn advance(&mut self) -> bool {
         self.token.text.clear();
         self.token.position = self.token.position.wrapping_add(1);
-
+        while let Some((offset_from, c)) = self.chars.next() {
-        loop {
+            if c.is_alphanumeric() {
-            match self.chars.next() {
+                let offset_to = self.search_token_end();
-                Some((offset_from, c)) => {
+                self.token.offset_from = offset_from;
-                    if c.is_alphanumeric() {
+                self.token.offset_to = offset_to;
-                        let offset_to = self.search_token_end();
+                self.token.text.push_str(&self.text[offset_from..offset_to]);
-                        self.token.offset_from = offset_from;
+                return true;
-                        self.token.offset_to = offset_to;
-                        self.token.text.push_str(&self.text[offset_from..offset_to]);
-                        return true;
-                    }
-                }
-                None => {
-                    return false;
-                }
             }
         }
+        false
     }
 
     fn token(&self) -> &Token {

src/tokenizer/stemmer.rs

@@ -2,7 +2,6 @@
 
 use super::{Token, TokenFilter, TokenStream};
 use rust_stemmers::{self, Algorithm};
-use std::sync::Arc;
 
 /// Available stemmer languages.
 #[derive(Debug, Serialize, Deserialize, Eq, PartialEq, Copy, Clone)]
@@ -57,14 +56,14 @@ impl Language {
 /// Tokens are expected to be lowercased beforehand.
 #[derive(Clone)]
 pub struct Stemmer {
-    stemmer_algorithm: Arc<Algorithm>,
+    stemmer_algorithm: Algorithm,
 }
 
 impl Stemmer {
     /// Creates a new Stemmer `TokenFilter` for a given language algorithm.
     pub fn new(language: Language) -> Stemmer {
         Stemmer {
-            stemmer_algorithm: Arc::new(language.algorithm()),
+            stemmer_algorithm: language.algorithm(),
         }
     }
 }
@@ -83,7 +82,7 @@ where
     type ResultTokenStream = StemmerTokenStream<TailTokenStream>;
 
     fn transform(&self, token_stream: TailTokenStream) -> Self::ResultTokenStream {
-        let inner_stemmer = rust_stemmers::Stemmer::create(Algorithm::English);
+        let inner_stemmer = rust_stemmers::Stemmer::create(self.stemmer_algorithm);
         StemmerTokenStream::wrap(inner_stemmer, token_stream)
     }
 }
@@ -109,15 +108,14 @@ where
     }
 
     fn advance(&mut self) -> bool {
-        if self.tail.advance() {
+        if !self.tail.advance() {
-            // TODO remove allocation
+            return false;
-            let stemmed_str: String = self.stemmer.stem(&self.token().text).into_owned();
-            self.token_mut().text.clear();
-            self.token_mut().text.push_str(&stemmed_str);
-            true
-        } else {
-            false
         }
+        // TODO remove allocation
+        let stemmed_str: String = self.stemmer.stem(&self.token().text).into_owned();
+        self.token_mut().text.clear();
+        self.token_mut().text.push_str(&stemmed_str);
+        true
     }
 }
 

src/tokenizer/stop_word_filter.rs

@@ -104,7 +104,6 @@ where
                 return true;
             }
         }
-
         false
     }
 }

src/tokenizer/tokenizer_manager.rs

@@ -1,4 +1,5 @@
 use std::collections::HashMap;
+use std::ops::Deref;
 use std::sync::{Arc, RwLock};
 use tokenizer::box_tokenizer;
 use tokenizer::stemmer::Language;
@@ -46,7 +47,8 @@ impl TokenizerManager {
             .read()
             .expect("Acquiring the lock should never fail")
             .get(tokenizer_name)
-            .map(|boxed_tokenizer| boxed_tokenizer.boxed_clone())
+            .map(Deref::deref)
+            .map(BoxedTokenizer::boxed_clone)
     }
 }